Hello, I'm using an Audiotrak Maya U5 USB card. As far as I can tell it is based on VIA EnvyUSB VT1728A chip. Running on fresh 3.5-rc7 or an old 2.6.32.27 (on openwrt) kernel I have similar problems with the mixer: 1. The controls PCM and PCM 1 are stuck on lowest level. It can play mp3s fine so I guess PCM is initialized somehow on proper levels but I would expect there should be a way to control PCM volume (other than by controlling Speaker volume). 2. I'm unable to achieve a 'loop' between SPDIF input and the Speakers. It works fine with Line-In. But with SPDIF input I have to either use "arecord | aplay" or alsaloop. Since Windows7 is able to turn on 'Listen' mode on SPDIF input on standard drivers I hope hardware can do it but somehow there is no control for this in alsamixer.
alsa-info output available at: http://pastebin.ca/2173999 (this is with with laptop's hda modules removed) (Latest Audiotrak firmware was installed)
Many Thanks, Rafal