[mythtv] Fw: [mythtv-users] Myth is locking soundcard andpreventing fullduplex operation

James Knight foom at fuhm.net
Wed Apr 16 12:19:40 EDT 2003


On Wednesday, April 16, 2003, at 10:29  AM, Edward Wildgoose wrote:
> Hmm, this was an excellent suggestion.  Just tried it and it works 
> fine -
> with xawtv I basically get live sound if I run this command
>
> I had a browse through the libmythtv code and it appears to only open
> read-only and write-only for record and play so there are no obvious 
> issues.
> There is some changing of modes though (frequency, etc) which could be 
> an
> issue?  The default record frequency from /dev/dsp appears to be 8khz.
>
> Any ideas on where to look next please?

Maybe your soundcard can't do simultaneous stereo capture and playback?

Try:

sox -t ossdsp -r 44100 -w -c 2 /dev/dsp -t ossdsp -r 44100 -w -c 2 
/dev/dsp
(you may have to install sox first)
or even perhaps:
arecord -f S16_LE -c2 -r44100 | aplay -f S16_LE -c2 -r44100

That should set most of the options Myth is using. 2 Channels, 
44100kHz, 16bit samples. If your sample rate is different in myth for 
record or playback you should change it on that command line too.

If *that* works even, my next guess is that perhaps you can't do 
something while the mixer device is open.

James



More information about the mythtv-dev mailing list