I am trying to record audio with the PS Eye on a raspberry pi model b plus (I have tried with older b models and the same issue occurs as below).
I am able to record, and playback the recording with arecord/aplay so the mic is working. However, I want to increase the mic volume as the recording is very low.
When I attempt this in alsamixer, it exits with the following error when I use F6 to change to the PS Eye soundcard:
cannot load mixer controls: Invalid argument
I also notice that the alsa-utils service will fail when the PS Eye is plugged in (fine otherwise):
sudo service alsa-utils restart [FAIL] Shutting down ALSA...warning: 'alsactl store' failed with error message 'alsactl: get_control:259: Cannot read control '2,0,0,Mic Capture Volume,0': Invalid argument'...failed. [....] Setting up ALSA...warning: 'alsactl restore' failed with error message 'No state is present for card CameraB409241 Found hardware: "USB-Audio" "USB Mixer" "USB1415:2000" "" "" Hardware is initialized using a generic method No state is present for card CameraB409241'...amixer: Mixer hw:1 load error: Invalid argument amixer: Mixer hw:1 load error: Invalid argument amixer: Mixer hw:1 load error: Invalid argument amixer: Mixer hw:1 load error: Invalid argument amixer: Mixer hw:1 load error: Invalid argument ... done.
The problem seems to be the controls definition of the PS Eye. I would like to know the following:
Where does alsamixer load the controls for a particular device from? Are they in the driver?
Is there a way to increase the mic volume another way?
I am not using Pulseaudio yet but will try it if I can't fix this in alsa.