[PD] help with mic input in linux?

[David Merrill]

Hi there -

I'm struggling to get microphone input into pd from linux.  I'm using 
ALSA, and the planet-ccrma version of Redhat 8.0 on an IBM thinkpad. 
 The main things I don't understand are:

- how do the settings in alsamixer affect how audio comes into PD?  (the 
main reason I ask is that when I boost the level of the mic and/or 
line-in in alsamixer, I *hear* the microphone/line audio coming out of 
the speakers of my PC, but so far I haven't been able to get PD to grab it)
- (relately), can I have the levels of mic/line turned down or even 
muted in alsamixer, but still get this audio into PD for processing? I 
don't actually want the audio to go straight through my system to my 
speakers (thus I want to turn down/off these levels in alsamixer), but I 
do want the audio to be available to PD for processing.
- is there any good way to figure out how "-audioindev" devices are 
numbered in linux other than trial and error?  (in the presence of my 
above problem, I'm not sure if "-audioindev 1" is any more likely to 
work than "-audioindev 10" based on the multitude of devices that show 
up in alsamixer..)

much appreciated!
-David Merrill