[mythtv-users] Live Audio

[Bruce Markey]

Russ Neufeld wrote:
> Thanks - I've read through all that stuff, and I'm quite sure my ALSA
> drivers are working correctly. However, perhaps it's changed or unknown
> language/terminology that's throwing me off...
> 
> My on-board Realtek ALC650 audio has a lot of controls I'm not sure of,
> and I'm a little confused by the CAPTUR part of the audio
> troubleshooter. Is that just referring to which source I check the
> "Rec." option (Gnome ALSA mixer) for, or is that something else I missed
> somewhere? I have a Capture mixer and it's 100%. Checking or unchecking
> the "Rec." option doesn't seem to matter.

Yes, it is a little confusing which is why hundreds of people
have been down this road before you. First, use "alsamixer"
from the command line so that we're talking about the same
thing =). Next, realize that the "CAPTUR" above the slider
to indicate which pair of things is involved in recording is
different than "Capture" below the slider that controls the
recording level. When you have this set right it should look
something like this. 

                      CAPTUR      CAPTUR
 +--+        +--+     L+MM+R      L+--+R
 |  |        |  |      |  |        |  |
 |  |        |  |      |  |        |  |
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 |##|        |##|      |  |        |##|
 +--+        +--+      +--+        +--+
Master  ...  PCM  ...  Line  ... <Capture>

This assumes that the patch cable from the line-out of the
TV card is plugged into the "Line" in for your sound card.

If Line was unmuted (by pressing "M") and the volume was turned
up, you should hear the realtime pass through sound. Of course,
you don't want to hear that while you are recording with myth.
Note that "Line" is marked for "CAPTUR" (by pressing "Space")
to indicate that it is the source for capture and the Capture
slider controls the volume of the recording.

If you still don't hear sound, plug speakers or headphones
directly into the line out of the TV card. If you don't hear
sound then there is either a bttv driver problem or you have a
defective card.

If you do have audio, plug the patch cable back in, unmute and
turn up Line and make sure that Master and PCM are unmuted and
turned up. If not, you may have a bad patch cable, ALSA driver
problem or a sound card with a bad Line jack or a defective DSP.

If you do hear the realtime sound but can't record with myth,
run myth's "setup" program and in Capture Cards make sure you
set the correct /dev/dsp* . Run mythfrontend and go to Setup->
TV Settings->Recording Profiles and check your settings for
LiveTV. 

Next, start the backend from a commandline and start the
frontend form another then go to Live TV If there is no
sound, check the console messages for both the front and
backend.

--  bjm