[linux-audio-user] aplay, plughw, alsamixer question

[Mark Knecht]

Hi,
   Hi. I asked this question on Alsa-Dev yesterday, but 17 hours later got
no answers. Excuse me to those that subscribe to both lists.

   This info is to help me do more debug work on a new HDSP 9652 driver
version that I am helping to test.

   Should the volume levels I hear when using the command

aplay -Dplughw:0 -r 44100 data/wave/seque~10.wav

be controlled by alsamixer?

The volumes for alsaplayer are being controlled by alsamixer, but this aplay
command is not, at least right now on a new driver I'm using.

   Also, on a multichannel card, how do I direct the above aplay command to
a specific channel? I am finding that with this new driver the audio is
appearing on ALL channels on the card, even for a mono wave file. I think
this is a bug, but I'm not sure.

   If there's an explanation fit for a simpleton like me about the
difference between plughw and hw and when to use one vs. the other, please
point me there so I can learn. I have read a bit on the Alsa site about
plughw talking directly to the kernel, but beyond that I have not discovered
any documentation yet.

   Thanks in advance.

Cheers,
Mark