> My confusion turned out to be with what exactly alsamixer > does. ?I was getting playthrough because the "Mic" device > was unmuted in the mixer. So alsa was doing the playthrough > directly. Well, because alsamixer is a tool which tries to match to all cards supported by ALSA, it is sometimes a bit confusing. But we do not have a better solution; ask your manufacturer to write a GPL'ed UI-Mixer for that certain device. > I somehow had the impression that one used alsa > mixer to set the input levels of various devices that were > available to be opened by software talking to alsa. What does various devices mean in this case? > But by > experimenting with audacity, I see that with Mic muted in > alsamixer, audacity is able to get input from the Mic > device via alsa. Does this imply that ALL input devices > should be muted in alsamixer and apps are responsible for > reading from the input? ?For example, it seems to not > matter whether I've muted the CD or not.. AlsaPlayer can > still play a CD. I guess that alsaplayer reads the CD and puts it out to PCM. The CD channel is if you have a CD inserted and you've pressed the play button on the drive. In this case, it behaves like a CD player. If it is connected via an extra cable to the mainboard, the drive will output the sound directly to the soundcard and then adjusting the CD channel would make sense. Best regards ce