[Alsa-user] microphone input volume control

[Tobias H. <tob...@go...>]

Hi all,

I'm working on a ThinClient (HP t5745) with an ALC272 sound chip and
analog speaker connected via analog headphones.
(Fedora 14, kernel 2.6.37, all modules compiled in, alsa driver 1.0.23)
Sound from every application is working fine. I'm able to adjust the
volume with alsamixer master volume slite.
But when I connect an external mp3 player (analog microphone in),
volume adjustment is only possible via mic slite.
I created certain different .asoundrc config files with dsnoop, dmix
and softvol, but no alteration.
It seems to me there is a analog pass through.
Is this a normal behaviour? Or is it possible to create a
configuration, which let me adjust the volume like all other things
via master control?

Hope someone could help.

Tobias

# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC272 Analog [ALC272 Analog]
 Subdevices: 0/1
 Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 3: HDMI 0 [HDMI 0]
 Subdevices: 1/1
 Subdevice #0: subdevice #0

# aplay -L
null
   Discard all samples (playback) or generate zero samples (capture)
default:CARD=Intel
   HDA Intel, ALC272 Analog
   Default Audio Device
front:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   Front speakers
surround40:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   4.0 Surround output to Front and Rear speakers
surround41:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Intel,DEV=0
   HDA Intel, ALC272 Analog
   7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
hdmi:CARD=Intel,DEV=0
   HDA Intel, HDMI 0
   HDMI Audio Output

http://pastebin.com/WJQCW8z5