[mythtv-users] Loud static for audio when pressing left-arrow (jump back) on mythtv 0.24

[Jean-Yves Avenard]

Hi

On 6 December 2010 08:01, Jeffrey J. Kosowsky <mythtv at kosowsky.org> wrote:
> Just upgraded from 0.23 to 0.24.
> Audio works fine on normal playback, but if I hit the left-arrow (jump
> back I think), then I get loud static with no audio until I press
> right-arrow (jump forward).
>
> As suggested, I ran the "Scan for audio device" which gave me the
> following settings: (which actually are pretty much what I had under
> 0.23)
>                                Audio output device: PulseAudio:default
>                                Speakers configuration: Stereo
>                                UNCHECK:Upconvert stereo to 5.1 surround
>                                CHECK: Advanced Audio Configuration
>                                        UNCHECK: Override SRC quality
>                                        UNCHECK: Force audio device output to 48kHz
>                                        UNCHECK: Separate digital output default
>
> (Note I am not sure of the exact wording of the advanced audio configuration
> options since the font appears as "squished" in my 800x600 MythCenter
> 1.1 box)

This is a frequent problem with PulseAudio when it resample the audio
, often it generates static.

Change the default resampling rate in the pulse audio server from
44.1kHz to 48kHz.

I haven't found a clear explanation as to why Pulse is doing so, other
than their resampler is seriously buggy...

Edit /etc/pulse/daemon.conf

and change the line as :
default-sample-rate = 48000

The other work-around would be when using pulse, to make myth resample
to the rate pulseaudio uses and ignore what pulse is supposed to
support.

But I really dislike adding workaround in our code for other's framework bugs

Jean-Yves