[mythtv-users] Sound stutters during dark video

[Michael T. Dean]

On 11/14/2006 02:46 AM, Mr. Demeanour wrote:
> Viitasaari wrote (and I re-arranged):
>   
>> On Mon, 2006-11-13 at 13:56 -0500, Michael T. Dean wrote:
>>     
>>> On 11/13/2006 01:31 PM, Mr. Demeanour wrote:
>>>       
>>>> When video fades to black, the audio starts to break up. When the
>>>> dark interval is over, the stutter goes away. This happens with
>>>> recorded matter as well as when watching "live" TV. It doesn't
>>>> always happen, but it does seem to be the usual case. The fade
>>>> doesn't always have to be a full fade to black - just a period of
>>>> relatively dark video is sometimes sufficient. The stutter
>>>> usually lingers for about a second after the video has become
>>>> bright again.
>>> In mythfrontend settings, Playback settings, page 1, "General
>>> playback":
>>>
>>> Extra audio buffering Enable this setting if MythTV is playing
>>> "crackly" audio and you are using hardware encoding. This setting
>>> will have no effect on MPEG-4 or RTJPEG video. MythTV will keep
>>> extra audio data in its internal buffers to workaround this bug."
>>>       
>> Would this be related to sound and video stuttering during a channel 
>> change?
>>     
> Not particularly. I have occasionally noticed momentary glitches during
> channel-changing, but it's not the same thing. For example, the
> phenomenon I am reporting doesn't involve any video stutter.
>
> Feedback: I have now set "Extra audio buffering", and spent a few hours
> watching. I haven't noticed any of this stuttering since I made the
> change, but I'm not yet ready to conclude that it's fixed.
>
> So thanks for the suggestion! However note that it wasn't at all an
> answer to my original question, which was roughly "what is the cause of
> this phenomenon?" - I like to understand the systems I use. In
> particular, if I don't know what caused it, then I won't know how to
> avoid future changes that might cause it to re-appear.

If you're not content that you've now fixed the problem, re-read the 
help text I included above that explains what the setting controls.  
Then, imagine what might happen if Myth didn't do what the setting makes 
it do.  Now, you understand "the cause of this phenomenon."

If you don't, get out your text editor and start reading the code.  I 
volunteered my time to respond with the fix for your issue.  If you want 
more, don't /expect/ it to be handed to you--be willing to put in your 
own time/effort.  Then, if you have specific questions, feel free to 
post them and /hope/ for a response.

Mike