[SOLVED] volume control bug when turning off DAC

[Tim Curtis]

The observation below would suggest the DAC may have a volume implementation thats not compatible with Linux/ALSA.

Code:

Another thing I noticed with the Loxjie D30 when used with "hardware" volume control, is that setting the volume in the Moode web UI doesn't update the D30's volume on its front panel screen. From this I conclude that Moode isn't changing the hardware volume of the D30 after all. Or perhaps the D30 has two hardware volume controls, one controlled by the knob, another controlled by the USB host. Not really sure.

For your steps, start by posting the output of the 2 commands after step 3.

1. Plug in Loxjie D30 via USB into the Raspberry Pi 4B running Moode 9.2.5 2025-02-23.
2. In Moode settings, set the D30 to the output device and select hardware volume.
3. Play some music and adjust volume to comfortable listening level. For my headphones, this was "45 (-21dB)" in Moode's web UI.

Code:

aplay -l

amixer scontrols

4. Switch OFF D30 by holding down physical volume knob on front panel.
5. Switch ON D30 by again holding down the physical volume knob.
6. Press play on Moode's web UI.
7. Now no audio is heard. Complete silence. This is unexpected to me.
8. If you go to Moode's volume panel in the web UI it displays "45 (-127dB)"
9. If you adjust the volume in Moode's web UI to anything other than the current value, audio comes back.