[mythtv-users] Understanding audio rates

[Michael Lynch]

I had a problem a while back where I had 2 cards in my backend that
required different sample rates.  The original thread can be found
here:

http://www.gossamer-threads.com/lists/mythtv/users/206982

Mike Dean suggested that I get a properly configured /etc/asound.conf
to remedy my problem, but I ended up just adding one of the cards to a
separate machine.  To remedy the problems when I had the cards in
different boxes, I just set up separate Recording Profiles that were
specific to each host.  One profile captured audio at 32kHz for the
saa7134 card and the other profile captured audio at 48kHz for the
bttv card.

Well, I've since had to put both cards back into the same system and
the problem is back with me.

To give an overview, I have 2 capture cards - Hauppauge WinTV Go
(bttv) and a Compro VideoMate TV Gold Plus (saa7134).  When the
recording profiles are set to 32kHz audio sample rates, the saa7134
card works perfectly but the bttv card has a horrible hum in the
audio.  When the recording profiles are set to 48kHz audio sample
rates, the bttv card works perfectly but the saa7134 card sounds like
chipmunks.

I appreciate Mike's suggestion that I need a properly configured
/etc/asound.conf but I am not sure that it pertains to my situation.
I am not using any digital audio or passthrough.  The backend in the
garage does the recording and the frontend in the house does the
playback.  If I play the files locally on my Windows laptop (using
VLC), the audio is still skewed as above, so that leads me to believe
that it's not actually the playback that is wrong, but my captures.

If I am wrong about the /etc/asound.conf file I definately need some
help with it.  Since it affects playback, I'm assuming I need it on
the frontend.  Here is the output from `aplay -l` on the remote
frontend:

**** List of PLAYBACK Hardware Devices ****
card 0: ICH5 [Intel ICH5], device 0: Intel ICH [Intel ICH5]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: ICH5 [Intel ICH5], device 4: Intel ICH - IEC958 [Intel ICH5 - IEC958]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
*****************************************************

If I in fact don't need the asound.conf file, any ideas on what I
could do to remedy this issue?