Re: [linux-audio-user] Disabling Playthrough

> 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
Received on Wed Jan 5 16:15:05 2005