Slimserver 6.2.* consumes too much cpu, and its slowness results in player timeouts and music hiccups.

I have disabled itunes, artwork, and anything else that looks like it might degrade performance, but:

1) When selecting a playlist for the first time the server spends so much of its time rescanning the playlist content that the player times out (squeezebox 1, wired).  This is very repeatable: just modify the playlist file and reselect it from the browse-music -> browse music folder -> (playlist file).  Subsequent replays of the same playlist do not timeout (cached i guess).  Playlist size is a mere 500 files, all .wav files (no tags).

2) As the music plays, almost any non-trivial activity on the same machine as the server is enough to cause short hiccups (temporary interruptions) in the music.  Even leaving the machine alone will still result in occassional hiccups.  These latter hiccups are not so deterministic, sometimes several within the span of 5 minutes, sometimes nothing for an hour or more.

I have about 200Gig of files, all .wav files, so only ~4k songs.  My machine is a p4-2.6Ghz, with 1Gig ram.  Previous versions (6.0) of slimserver worked fine, without either of the above problems, and my playlists have not changed appreciably.  The network is wired, 100Mbps and i've observed no network flaws.  Problems began with 6.2.0, but i tried upgrading to 6.2.1 and then to 6.2.2 but nothing helps.  Network/server health plugin shows near optimal behaviour, but when a new playlist is loaded there is a burst of lack of bufferfullness, and after playing for a while and experiencing several hiccups the plugin also says there are occasional problems with server response.  Sadly, it doesn't suggest anything i can do about that, or why that might be happening.

I have tried increasing the sql cache size to 30000 and then to 50000, and dropping the number of items built in each pass to 4 then 3.  This has had minimal impact---maybe the hiccups are less frequent, hard to say. 

During the server hiccups the machine running the server is noticeably slower (mouse movement becomes momentarily jerky).

The log file shows no errors.  Turning on various debug options results in the log filling up with messages about rescanning, but none look like errors.

I tried downgrading back to 6.0, but got lots of errors and the server refused to start.  Sigh...this all used to work so well...