NOTE: This happens with both the analog outs and the digital out fed to an outboard DAC.

Denis, are you using native FLAC playback or are you transcoding to WAV or perhaps MP3 on the server?  You can check by going to Settings > Advanced > File Types in the web interface.

It's set to native. Specifically, under the "FLAC" file type, FLAC is set to native, mp3 is disabled, and WAV is flac.

Alan, does this sound familiar to you and would any for your streaming enhancements slated for future releases possibly fix this?

Denis, would it be possible to temporarily run your Squeezebox on Ethernet to see if you get the same behavior?

I have not been able to reproduce this myself.

This bug was submitted after 4 months of extensive testing with customer service. I ran it wired and could not get it to happen. It's so intermittent that it's hard to test, yet it's so loud that I'm afraid it will fry my system.

This happened about the same time when I was experiencing mysterious halting of playback, where the Squeezebox gets frozen with no output, but when you check the Squeezecenter, the playback time loops over a 3-5 second period. I will be submitting a separate bug for this, since this is easily reproducible.

No, I cannot say how any of my proposed changes would help here since I have no idea what could be causing the current problem.

Denis, did we at some point replace your player?  Since you're the only person that seems to be seeing this, it's tough for us to know what to do about it.

Thanks for any info!

Yes, the player was replaced and the behavior persisted (this was in my original report). Please note that I reported this bug after researching this repeatedly by doing forum searches and trying various things out. I figure I'm not the only one, and as a fan of the product, I wanted to help out the community by seeing this through customer service and through proper bug fixing.

In any case, let me know if there's anything I can do to try and diagnose the problem. I've posted debug logs before to customer service, but they don't indicate any coincident events. Being a software engineer, there's even a possibility that I could compile the software and run a live debug.

I am still at a loss to understand what could be causing the intermittent burst of white noise.

Chris, is there anyone you can suggest that might have an idea of what might be happening here?

Felix, any ideas about this?

I'm actually experiencing a very similar bug.  During playback I have gotten either a burst of white noise (never >1 second long) or the song will skip to a random point (sometimes both).  I thought this might be a network connectivity issue but checking the Squeezeserver always indicates a network strength of 99%.  Network test on the player at 5000 kbps averages 92% and does not appear to ever dip below 70%.  The loudness of the burst sounds several times the volume of the actual music.

Most of my collection is in FLAC so I haven't been able to verify if it is a FLAC-only problem, but it seems suspect.

I believe this happened with Squeezecenter 7.0 also, but prior versions of Slimserver have not caused this.

What makes this sound like the same issue is that randomly the player will stop playing in the middle of a song.  This has happened on at least 2-3 occasions in the last 10 hours of so of playing (not continuous).

Yes, it sounds similar. After thinking about it, the bursts I experience are probably <1 second as well. They just seem longer because they are so damn loud. And you can see the burst in the pseudo-equalizer display, where the peaks hit the top of all the bands.

I tried wired for a little while and couldn't get it to recur. And I never had this happen back on earlier versions (6.5.2?), and I rolled back to various older versions. That didn't work, unfortunately.

BTW, I'm almost 100% FLAC. There are others that are experiencing the same problem on the forums. If you search for "static" or "white noise" or "screech", you'll see related postings; some of those people seem to have tried various fixes to varying degrees of success. I've tried them all with no luck.

A bit more info:

Squeezebox v3, RCA outputs
Linksys WRT54GL router

The player stopping occurs much more frequently than the burst of noise.  But
the latter is much more concerning with regard to damage to speakers.

Sorry...just remembered something else that might help troubleshoot:

About a week ago when I changed from digital to analog outputs (to feed into dedicated 2 channel preamp/amp) I encountered streaming issues where one song would play, the next song would start playing, but the display would not change and the Squeezebox actually seems to "freeze" for about 5-10 seconds.  This seemed to get worse to the point where scrolling through albums would also "freeze" for a similar period of time.  I suspected it was a network connectivity issue, but neither the player nor the server reported any info to that effect.

This seems to have gone away with the upgrade from 7.0 to 7.0.1.  I don't think I got the bursts of noise until 7.0.1 (just had skips/stops), but since it's a rare occurrence that I haven't been able to reproduce reliably, it could simply be a matter of chance.

You mention the bursts are loud.  Are they louder than the music?  That is, if the music is playing relatively quietly are the bursts still really loud?  That might help find the source of the noise as logically before or after the volume scaler... or it might not.

(In reply to comment #15)
> You mention the bursts are loud.  Are they louder than the music?  That is, if
> the music is playing relatively quietly are the bursts still really loud?  That
> might help find the source of the noise as logically before or after the volume
> scaler... or it might not.
> 

To be honest, I think it's only happened twice, but both times the music volume was probably around normal listening volume.  The burst of noise sounded significantly louder than the music though -- much louder than I've ever turned up my speakers, in fact -- so I'm tempted to say that it was irrespective of volume, though I can't say so for sure.

Thanks for looking into this!

I'll chime in here to say that loud means LOUD! As I said earlier, the bands of the meters all hit peak. It's as if the Squeezebox was mistakenly fed a packet with all 1's for audio data.

And although Tairan experienced it only a couple of times, I've heard it dozens of times over the past year.

What OS and versions is this happening with?  We have so far not been able to reproduce.  Does it happen consistently with some of the same FLAC files?

I'm using Windows XP and this seems to happen with any version 7 release of Squeezecenter, irrespective of the specific file that's being played back.  I installed the latest 7.1 last week and, while I have not gotten the burst of white noise yet, I have encountered the problem where tracks would randomly skip ahead, which appears to be a related issue in that I also have not encountered this prior to version 7.  I can't say I noticed this happening with the 6.5.x versions, but I have not reverted my software to check...

I'm on XP as well. I've heard the screech since the 6.5.x days, and have continued to hear it on 7.0. I even reverted to what I thought was a version that didn't have the problem (6.5.1?), but it remained.  I also tried resetting the Xilinx chip, even swapped the units with customer service, to no avail.

It doesn't have anything to do with particular files, since it's never repeatable. I've sent flacs that were playing when the screech happened to customer service before, and they could not reproduce the problem (as anticipated). 

Another point worth reiterating: the problem is through the analog outs as well as the digital output.

That being said, I haven't heard the screech in the past couple of weeks. 

What are your fade in/fade out settings?  Playlist shuffle turned on?  Is the music stored on a local hard drive or a network drive?

Never use fade in/out. Never use playlist shuffle. All files on a USB 2.0 External hard drive.

Don't use fade in/out either, and I believe I've seen this happening regardless of using random or album play.  My music is all on a local hard drive on the server.

Denis, what model of wireless router do you have?  Have either of you noticed if this happens only when your servers are busy (CPU or hard drive)?

Not sure if it might be because of CPU or HD load on the computer since my Squeezebox and computer are in different rooms.  I don't have much running usually and my computer is only a year old, so I wouldn't think that the CPU would be an issue.  It's possible that the hard drive might be an issue...free space on my music drive has recently dipped below 10% of total.

Do you suspect that it's an issue with the Squeezebox firmware or the server software?

How big is the internal data buffer in the Squeezebox?  I would think that, if the buffer ever runs low, the player would just stop until more data is received instead of skipping ahead randomly or coughing up a burst of noise.  Or maybe the Squeezecenter software is inserting bad data?

Yeah the units have about 7 megabytes of buffer, and I'm pretty familiar with the failures modes for when there is an underrun :)  There are pauses and 'breaks' in the music, not noise, just as you say, Tairan.  

There is a buffer fullness display which can be enabled in Settings -> Player -> Basic Settings, but I doubt it will show anything but a full buffer.  You can check it out just to make sure, if you want.

The noise failure mode would seem to point to a bug in the flac decoder of the device firmware, not in SqueezeCenter.

This just seems to be one of those bugs that needs a bit more detail before we can reproduce it.  I'll keep trying.  :)

Here's an interesting question: what program(s) do you use to rip your files?  Do you put any unusual tagging data in?  Embedded album art?

(In reply to comment #26)
> Yeah the units have about 7 megabytes of buffer, and I'm pretty familiar with
> the failures modes for when there is an underrun :)  There are pauses and
> 'breaks' in the music, not noise, just as you say, Tairan.  
> 
> There is a buffer fullness display which can be enabled in Settings -> Player
> -> Basic Settings, but I doubt it will show anything but a full buffer.  You
> can check it out just to make sure, if you want.
> 
> The noise failure mode would seem to point to a bug in the flac decoder of the
> device firmware, not in SqueezeCenter.
> 
> This just seems to be one of those bugs that needs a bit more detail before we
> can reproduce it.  I'll keep trying.  :)
> 
> Here's an interesting question: what program(s) do you use to rip your files? 
> Do you put any unusual tagging data in?  Embedded album art?
> 

I've used various versions of Exact Audio Copy to rip to WAV, and it calls the native FLAC encoder .exe to encode.  I tag my files using foobar2k and only fill in Artist, Track, Album, Date, Genre, Track/Disc #, Total Tracks/Discs, and the Comment fields.  Album art is a separate folder.jpg.

Thanks for investigating this!  I have not been able to reliably reproduce this.  Since I reported the bug I've only heard the burst of noise once, but I've gotten the strange random skip issue a number of times.

Let me see if I can answer the various questions:

- I use EAC with the FLAC settings that the original 6.5.1-era wiki instructions had. I haven't changed them since. I don't do anything (consciously) with tagging or with album art.

- I use a Linksys WRT54G. I replaced it recently when I had connectivity issues.

- Interestingly, I had an screech this weekend that could provide some clues. The wireless router is upstairs, and I usually only get ~33% signal strength. I had two episodes of the playback stopping mid-track. The first time was typical; the Squeezebox just kept thinking it was still playing the track, but was hung in an endless loop. The second time, an error message showed in the display indicating a lost connection." Later, I started getting stuttering (buffer underun), then a SCREECH. I continued to play with some stuttering, and I found out that my son was using the computer. Turns out that he had been typing in WORD and not streaming or burdening the PC. I had him move away from the computer for 5 minutes, and the stuttering went away. 

The point of the last anecdote is that I would guess that there's an issue with improper handling of packets when there's an underrun of the buffer, or there is a problem with handling network drop outs. Of course, this is just speculation.

I was thinking this was buffer/network-related too, but also have very little on which to base this.  A lot of variables changed before I first heard the burst of noise:

- changed location of Squeezebox (TV stand to floor -- in process of moving)
- switched from digital to RCA out
- upgraded to SC version 7

It does seem very coincidental, however, that the burst of noise bug started occurring around the same time that I got random skipping (Squeezebox fast forwards to random part of a song), stuck tracks (Squeezebox just stops playing in the middle of a song and does not resume), and the displaying freezing when changing tracks.  The latter 2 hasn't happened in a while, and checking the network status right after said error always gives above 80% signal strength -- neither of these provide any evidence to the contrary, of course.

Ping Chris!

I'm moving the target for this bug.  We'll keep looking at it but I don't want it to hold up the 7.2 release.

Ross, did you say you had a particularly slow PC set up with SC?  I'm not saying that's the cause, but I wonder if this would be easier to reproduce in that case.

Yes Wallace has one, it's in the corner of the QA lab closest to Randy's office. 

If you were referring to me (the bug originator), then it is possible that my "slow" PC could be contributing. I believe it is a P4 at 1.8 or 2.0Ghz (I remember the BIOS being from 2002). It's definitely a senior citizen.

Some minor data points:

- I bought a DUET, and have never heard the screech. I have definitely seen some problems with the DUET getting mixed up about what track its playing, but that seems unrelated to this bug.
- I moved the Squeezebox 3 to a different location in the house with a much stronger wireless signal, and it still screeched at least once already.

FYI, and thanks for continuing the bug hunt.

-Denis

I'll add my recent experiences:

- My PC is a dual core @ 2.13 ghz with 4 gigs of RAM, only maybe a year or two old at this point.
- I just started using a ReadyNAS NV+ as the music server.  It is appreciably slower but so far have not experienced any negative symptoms except for interface lag.
- I haven't heard the screech in a long time now.  However, prior to switching to the ReadyNAS NV+ I was still reliably getting the random skip.  Songs will end and go to the next track inexplicably.  (Not sure whether I should start a new bug for this or if a more closely matching bug thread exists?)  I'll post back once I've used the ReadyNAS a bit more to see if the situation might have been isolated to my computer.

I can report this bug happening when my partner (in Australia) uses her Softsqueeze to stream from my Squeezecenter (which is with me in the US) -- while I'm also listening to my SB2 (using its digital outs).  

Since I listen on headphones, this might have destroyed my hearing (and her PC speakers and my Senn HD650 headphones).  My ears are still ringing loudly.  Investigating, with the volume low, the trigger seems to be when I set Bitrate Limiting on her player (Softsqueeze).  

My collection is entirely FLAC.  To stream to AU I set it to 128 with lame.  The very LOUD "whitenoise" will come from both my headphones and her computer and it will persist until I shut down Squeezecenter.

SqueezeCenter Version: 7.2.1 - 23630 @ Tue Oct 21 07:44:57 PDT 2008 - Windows XP - EN - cp1252
Server IP address: 140.180.18.78
Perl Version: 5.8.8 MSWin32-x86-multi-thread
MySQL Version: 5.0.22-community-nt

Platform Architecture: 586

Hostname: aristurtle

Server Port Number: 9000

Total Players Recognized: 2


Name: Ilana's home

Model: softsqueeze

Firmware: 2

The IP address for this player is: 220.233.122.140:49553

The Ethernet MAC address for this player is: 33:8e:96:63:2f:3b

Name: Simon's Head

Model: squeezebox2

Firmware: 113

The IP address for this player is: 192.168.0.2:46660

The Ethernet MAC address for this player is: 00:05:30:55:91:5f

Just to be clear:

Switching on BITRATE LIMITING on the Softsqueeze player immediately causes loud and persistent noise exactly as described in this thread to come from both my SB2 and the Softsqueeze.  

If I leave off Bitrate Limiting the error doesn't occur, but unfortunately the Softsqueeze player in Australia will skip when the connection isn't fast enough to support lossless streaming!


(In reply to comment #36)
> I can report this bug happening when my partner (in Australia) uses her
> Softsqueeze to stream from my Squeezecenter (which is with me in the US) --
> while I'm also listening to my SB2 (using its digital outs).  
> 
> Since I listen on headphones, this might have destroyed my hearing (and her PC
> speakers and my Senn HD650 headphones).  My ears are still ringing loudly. 
> Investigating, with the volume low, the trigger seems to be when I set Bitrate
> Limiting on her player (Softsqueeze).  
> 
> My collection is entirely FLAC.  To stream to AU I set it to 128 with lame. 
> The very LOUD "whitenoise" will come from both my headphones and her computer
> and it will persist until I shut down Squeezecenter.
> 
> SqueezeCenter Version: 7.2.1 - 23630 @ Tue Oct 21 07:44:57 PDT 2008 - Windows
> XP - EN - cp1252
> Server IP address: 140.180.18.78
> Perl Version: 5.8.8 MSWin32-x86-multi-thread
> MySQL Version: 5.0.22-community-nt
> 
> Platform Architecture: 586
> 
> Hostname: aristurtle
> 
> Server Port Number: 9000
> 
> Total Players Recognized: 2
> 
> 
> Name: Ilana's home
> 
> Model: softsqueeze
> 
> Firmware: 2
> 
> The IP address for this player is: 220.233.122.140:49553
> 
> The Ethernet MAC address for this player is: 33:8e:96:63:2f:3b
> 
> Name: Simon's Head
> 
> Model: squeezebox2
> 
> Firmware: 113
> 
> The IP address for this player is: 192.168.0.2:46660
> 
> The Ethernet MAC address for this player is: 00:05:30:55:91:5f
> 

Final update! 

I've just tested this with the latest nightly build of 7.3 and the problem persists.  Whenever Bitrate limiting is switched on, the Softsqueeze client makes loud white noise.  If I am also listening on my SB2 (to something different, the two arn't synched), the whitenoise sounds there too.

(In reply to comment #37)
> Just to be clear:
> 
> Switching on BITRATE LIMITING on the Softsqueeze player immediately causes loud
> and persistent noise exactly as described in this thread to come from both my
> SB2 and the Softsqueeze.  
> 
> If I leave off Bitrate Limiting the error doesn't occur, but unfortunately the
> Softsqueeze player in Australia will skip when the connection isn't fast enough
> to support lossless streaming!
> 
> 
> (In reply to comment #36)
> > I can report this bug happening when my partner (in Australia) uses her
> > Softsqueeze to stream from my Squeezecenter (which is with me in the US) --
> > while I'm also listening to my SB2 (using its digital outs).  
> > 
> > Since I listen on headphones, this might have destroyed my hearing (and her PC
> > speakers and my Senn HD650 headphones).  My ears are still ringing loudly. 
> > Investigating, with the volume low, the trigger seems to be when I set Bitrate
> > Limiting on her player (Softsqueeze).  
> > 
> > My collection is entirely FLAC.  To stream to AU I set it to 128 with lame. 
> > The very LOUD "whitenoise" will come from both my headphones and her computer
> > and it will persist until I shut down Squeezecenter.
> > 
> > SqueezeCenter Version: 7.2.1 - 23630 @ Tue Oct 21 07:44:57 PDT 2008 - Windows
> > XP - EN - cp1252
> > Server IP address: 140.180.18.78
> > Perl Version: 5.8.8 MSWin32-x86-multi-thread
> > MySQL Version: 5.0.22-community-nt
> > 
> > Platform Architecture: 586
> > 
> > Hostname: aristurtle
> > 
> > Server Port Number: 9000
> > 
> > Total Players Recognized: 2
> > 
> > 
> > Name: Ilana's home
> > 
> > Model: softsqueeze
> > 
> > Firmware: 2
> > 
> > The IP address for this player is: 220.233.122.140:49553
> > 
> > The Ethernet MAC address for this player is: 33:8e:96:63:2f:3b
> > 
> > Name: Simon's Head
> > 
> > Model: squeezebox2
> > 
> > Firmware: 113
> > 
> > The IP address for this player is: 192.168.0.2:46660
> > 
> > The Ethernet MAC address for this player is: 00:05:30:55:91:5f
> > 
> 

I meant to post an update to my situation.  I purchased a ReadyNAS NV+ a month or so ago and I've been using it as my music server.  Since I switched over to that, I haven't encountered the random skipping/white noise issues I've reported here.  I will keep a lookout and report any evidence to the contrary.

Simon, I really cannot understand how configuring bitrate-limiting for the SoftSqueeze instance, and not for the SB3, without the SoftSqueeze and SB3 being synced can affect the SB3 output.

Are you really saying that, you can be listening to SB3 and then configure bitrate-limiting for the SoftSqueeze instance and immediately, before either the SoftSqueeze instance or SB3 start playing a new track, the (unsynced) SB3 starts producing noise?

You originally report that this happened on SC 7.2.1, so I guess that rules out all the new-streaming and transcoding changes in SC7.3.

Nonetheless, I have tried to reproduce this with he latest SC 7.3 build on Linux and cannot. Ross, can you please try on a Windows platform as reported by Simon.

> Are you really saying that, you can be listening to SB3 and then configure
> bitrate-limiting for the SoftSqueeze instance and immediately, before either
> the SoftSqueeze instance or SB3 start playing a new track, the (unsynced) SB3
> starts producing noise?


Alan, 

As I recall, this is exactly right. 

After further experiments: to get the noise to _stop_ you must turn off bitrate limiting _and then change tracks_.  To get it to start you do not need to change tracks or wait for the next track to begin; it will begin immediately on both the SB2 and Softsqueeze as soon as bitrate limiting is engaged.  (I'll double check tonight, but I'm fairly sure this is right)

(In reply to comment #40)
> Ross, can you please try on a Windows platform as reported by
> Simon.

Far as I can tell Simon's reproduction steps are to stream FLAC to an SB3, stream FLAC to SoftSqueeze (not synced) and enable bitrate limiting for the SoftSqueeze client, then between tracks there should be a burst of white noise. I tried this on XP and I hear no burst of white noise. 

Simon, is my summary correct?  

I just want to make it clear that Simon's problem sounds like a different bug. Both bugs share in common the potentially damaging noise (to eardrums or audio equipment), which probably comes about from feeding some form of inappropriate digital data to the DAC's. Unfortunately, my bug is intermittent and the noise is short-lived (1-2 seconds), as explained earlier. 

Simon's bug is clearly different in the sense that it puts the software into a state that generates the noise, until he does something to change the system state.

>Far as I can tell Simon's reproduction steps are to stream FLAC to an SB3,
>stream FLAC to SoftSqueeze (not synced) and enable bitrate limiting for the
>SoftSqueeze client, then between tracks there should be a burst of white noise.
>I tried this on XP and I hear no burst of white noise. 

The noise occurs immediately once bitrate limiting has been enabled -- there is no need to wait for the track to change.  It will only _cease_ once bitrate limiting has been disabled, and the next track begins.

Also, my SB3 is connected directly to my laptop (not a router) via ethernet.

Alan Says:

I think that this is both (a) sufficiently odd, and (b) sufficiently bad if it is true, that it merits getting someone of the phone to him to really get to the bottom of what is going on.

I cannot imagine how saving a player-specific-settings-change for player-B could cause the sound coming from player-A (which is not synced to B) to change, but he has confirmed that this is exactly what is happening.

---------------------------

Ross:  Can you try to get to the bottom of this?

Changing target to next release

My SB3 arrived today and I have the same problem as described here. Loud noise (louder then normal music). Tried different versions of SqueezeCenter (7.3.1, 7.2.0, 7.2.1) but no difference. It occurs wireless (strength 78%) and attached with a 2m cable. It happens with FLAC and MP3.

Also got the loop (starts over and over again the first 5 seconds of the song, with a lot of noise) when playing FLAC without enabling bitrate limiting.

I'm using Windows XP and use a Linksys WRT54G wireless router.

Any sign of a solution?

Installed Squeezecenter (7.3.1) on an other Windows XP machine (in same network) and same problems occurs.

Now trying to get a linux machine up and running to see if the problems stays.

As the originator of the bug, I wanted to post an update. My original PC running XP died, and I replaced it with a dual core PC running Windows Vista. It's been about 2 months, and I haven't heard the screech. 

All of the networking components (e.g. the Linksys router, the firewall) remained the same. The OS is different, and the PC is faster, although there is only 1gig for memory. As I said before, I have had this system in place for 2 months with no incidences. That being said, the white noise was so infrequent for me, that it's hard for me to conclude that the problem is gone, although I am hopeful.

Thanks for sharing Denis, good to hear it's no longer a problem for you. 

Remko, anything new?

Thought I'd pitch in as well.  This problem seems to have gone away for me too since I started using my ReadyNAS to host my music collection.

I'm a little confused, is this bug resolved and can be closed?

Both Tairan and Denis replaced their servers, and they aren't hearing it any more. I've never reproduced it. I'm interested to hear how Remko is doing. 

Remko are you still able to reproduce? Did you learn anything interesting with a linux server?

Installed Ubuntu and problems stays. Also bought a NAS (Synology DS209+) and installed Squeezecenter on the box (Synology package and SSODS) but still same problems.
Also bought new router (D-Link DIR-655) but also same results.

So Squeezecenter v7 and above is not working, Slimserver 6.5.4 everything is working fine.

FYI.

Also placed a ticket at the support desk of Logitech. They advised me to call the support desk. Are going to this on Friday (wanted to wait the result of the router).

Remko have you ever heard this with Squeezebox Server installed on a PC? Is it safe to say this is isolated to the Synology NAS? 

Alan, could latency cause something like this? QA hasn't been able to reproduce this as of yet.

%d is not the sample rate of the current file. It is the sample-rate to which it must be downsampled if the player does not support the sample-rate of the source file. It will be an empty string if down-sampling has not been determined to be required.

Sorry, wrong bug.