Hello!

FIrstly, I've never used a mailing list before, so forgive me if I deviate from 
standard posting etiquette :p

After installing Debian lenny, my 4th order of business was getting sound 
working.
My soundcard is the m-Audio Revolution 7.1.

Problem1: only getting sound from front speakers
Fixed by: Google, looking in alsa.conf
Result: speaker-test -D plughw:0 -c 8 -twav
# I'm able to get sound out of all outputs on the Revo7.1, including stereo 
from the coaxial sp/dif. It should be noted, however, that hw:0 fails, as does 
plug:surround40, and others. Floating point errors and such.

Problem2:
alsamixer. Big problem this one.
The front speakers are controlled by "PCM", which is a sliding scale from 
-34.15 dB to 0 dB. The *very lowest* setting is loud. This is setting "2<>2" in 
alsamixer. Or 2% of full volume. Anything higher is too loud. In fact, on the 
default setting of 75%, my headphones blew up, and now I need to buy a new 
pair. Good thing they were cheap ones...

The next control is "PCM Cent". It's adjustment scale is -125 dB at the low 
end, and 0 dB at the high end. Unlike "PCM", it has no mute control. The other 
channels "PCM LFE", "PCM Rear", "PCM Side" are of the same scale as "PCM Cent". 
At 80% they are sufficiently loud. In fact, at 80% they are still quieter than 
PCM at 2%.

So what I think is going on is this:
1. Either the front speakers channel on the Revo71 uses different hardware to 
the other channels on the card =or=
2. alsamixer is configured wrong.

Is "PCM" supposed to be the master volume, and not tied to the front channel? 
It would explain the different dB scale it uses.
If "PCM" is indeed supposed to be Master volume, then I'm also missing a "PCM 
Front" slider in alsamixer. Hopefully this would use the same scale as "PCM 
Rear", etc.

Now I've Googled for hours today about this, as well as trying to decipher the 
rather cryptic alsa conf files. But to be honest I'm not sure where I should be 
looking.

As a confirmed Windows XP user, I've never had to relate to my soundcard on 
such an intimate level, as XP and m-A's drivers have done it all for me. Guess 
I'm a bit spoiled, then.

I should also note here that I did, in my investigations, find such files as 
/usr/share/alsa/pcm/front.conf, etc. It looks to my untrained eye that there 
*should* be a "PCM Front" control, but somewhere along the line the controls 
haven't been matched up properly on my system. Additionally, reports from other 
users of having a "Master Volume" slider in alsamixer would seem to support 
that theory. I have no "Master Volume" slider. "PCM" is the first on the list.

I don't mind trawling through the docs if it would lead to understanding ALSA 
more fully. But I'd love to hear what you suggest, and where I should start 
looking.

Regards,
k9
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