Music choice channels from Comcast are mpeg2 video which internally
identifies as 30 fps but actually sends frames with intervals
5.939, 0.033, 0.033, repeat, ... This amounts to 3 frames at 30fps
every 6 seconds. These frames are never identified as key frames.
Tuning takes up to 8 seconds for these channels on CETON. This
stream breaks several MythTV timeouts, and causes havoc with the
audio-video synchronization routines. It causes the recorder to
report a great many 6 second gaps in the video and mark it as failed.
Fix: Increase timeouts. Increase audio buffer size to allow up to
8 seconds to be buffered. In the backend allow recordings to start with a
non-key frame and set a high threshold for gaps in specific cases.
Change handling of video buffer waits so that audio data is not lost by
audio resets in music choice programs.
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