Correction: Bug 1397, Comment #75

This bug concerns a further enhancement of the "disable outputs when off" capability. Some receivers still interpret our S/PDIF output as being active when we try to disable them. These receivers seem to be detecting the input electrically, as opposed to using an s/pdif receiver chip to test for a valid signal.

What is desired is that when disabling s/pdif outputs, that we not merely ceaqse transmitting a valid carrier, but that any electrical modulation of the outputs be stopped. The coax output would go to 0 volts DC, and for the LED would turn off.

Note to Slim QA: the Digliyzer can NOT be used to test this. It doesn't know the difference between "no carrier" and "no voltage".

In addition to the need for 0V on the output to support some DACs, there is another useful side-effect of doing this. The presence or absence of a voltage on the SPDIF output could be used (via a suitable external device) to trigger power to ancilliary devices such as amplifiers. Felix's PowerSwitchII plugin can be used for this purpose on the Squeezebox Classic and Transporter, but not on the Squeezebox Receiver (since it has no headphone output).

Consider for 7.3.1.  Sean?

Still not able to automatically switch my Musical Fidelity X-DAC v3 by turning off receiver inputs.  I guess the DAC uses current sensing rather than spdif receiver chip to check for signal. I'll have to wait for 7.3.1  :-(

Changing target to next release

As with comment #5, I have a Mobile Fidelity X-DAC V3, which I have hooked up to the digital output of an SB3. (running 7.3.2)  I have the player's settings configured to "disable outputs when off."  When connecting the player to the DAC with the SB3's power off the DAC still detects a live input.  This occurs with both the coax and optical outputs of the player.

As a sanity check, I also connected the DAC to the digital output of my DVD player.  As expected, with both digital and coax inputs, the DAC indicates that the there is no live input when the DVD player is powered down. (confirming that the DAC is able to accurately identify the presence of a live input)

I have completely the same situation as described in #7. The only difference is that I am using a different DAC: Musical Fidelity X-DAC V2. Everything else said in #7 applies in my case too.

All new Squeezebox products are likely to be based on the SqueezePlay platform.
We do not plan to implement any further enhancements to the ip3k firmware or
which are targeted specifically at ip3k-based products.