[pvrusb2] pvrusb2-mci-20070114 radio support - stereo?
pakt223 at freemail.gr
Sat Jan 27 10:47:50 CST 2007
> So, if the audio mode present and settable is "Mono", how is the overall
> audio stereo? Is the value of ctl_audio_modes_present/cur_val decided by
> the signal strength? Signal strength should be same between whether I am
> booted in linux or windows, right?
Well, this is the difference between what the demodulator demodulates
and what the encoder encodes. If ctl_audio_modes_present/cur_val
is Stereo it means a stereo signal was autodetected. This is not a user
writable setting. Some stations broadcast mono, so signal strength
is not necessary playing a part here (though it might).
So, set ctl_audio_mode/cur_val to Stereo (or just leave it alone if you
haven't touched it). Same with ctl_mpeg_audio_mode/cur_val.
Just change frequencies until the ctl_audio_modes_present/cur_val is Stereo
and then repeat the test, please :-)
> I did the 'mplayer -vo null -ao alsa -af pan=2:1:1:-1:-1 /dev/radio0'
> experiment and I hear "squeaking noises like from a tape bewing in
> extremely fast forwind most of the time."
Yep, but unfortunately your result is meaningless because you used
a mono source, or the signal wasn 't strong enough for the demodulator
to detect stereo.
> I wish I could help more to find the exact cause of the audio problems, but
> now you have another data point and tester....;-)
Thanks a lot for testing :-)
Please repeat as above :-)
Oh, and please post the kernel/driver version you are testing :-)
Btw, results from people with 29xxx devices would be nice as well ;-)
It would be great if someone found a kernel version that passes the test
(anecdotal evidence suggests 2.6.15 may actually work). If this is found
to be a regression then knowing which is the last kernel version that works
will be *huge* help!
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