[mythtv] Mythtranscode HLS/AVF heavily distorted output

[William Wilhelm]

Ever since 0.27 -> 0.28, mythtranscode --avf/--hls has been giving very 
distorted output for transcodings of FTA recordings here in Australia.
Prebuilt "nightlies" from Mythbuntu and my own weekly builds from master 
both experience this issue. Audio is unaffected.

All channels are affected except for ABC News 24 and SBS 2.
To describe heavily distorted more: http://i.imgur.com/hfgrn2i.png.

Here is mythffprobe output for an affected recording file before 
transcoding:

ffprobe version v0.28-pre-2986-g004b87d Copyright (c) 2007-2014 the 
FFmpeg developers
   built on Jul 25 2015 11:49:45 with gcc 4.9.2 (Gentoo 4.9.2 p1.0, 
pie-0.6.2)
   configuration: --python=python2 --enable-libx264
   libavutil      52. 92.100 / 52. 92.100
   libavcodec     55. 69.100 / 55. 69.100
   libavformat    55. 48.100 / 55. 48.100
   libavdevice    55. 13.102 / 55. 13.102
   libavfilter     4. 11.100 /  4. 11.100
   libswscale      2.  6.100 /  2.  6.100
   libswresample   0. 19.100 /  0. 19.100
   libpostproc    52.  3.100 / 52.  3.100
[mpegts @ 0x6a5020] write_section_data: PID 0x901 CRC error
[mpegts @ 0x6a5020] write_section_data: PID 0x322 CRC error
[mpegts @ 0x6a5020] write_section_data: PID 0x901 CRC error
[mpegts @ 0x6a5020] write_section_data: PID 0x322 CRC error
[NULL @ 0x6ab2a0] start time for stream 3 is not set in 
estimate_timings_from_pts
[NULL @ 0x6acf80] start time for stream 4 is not set in 
estimate_timings_from_pts
[mpegts @ 0x6a5020] write_section_data: PID 0x901 CRC error
[mpegts @ 0x6a5020] PES packet size mismatch
Input #0, mpegts, from 'fails2.ts':
   Duration: 00:00:08.44, start: 95228.329600, bitrate: 4911 kb/s
     Stream #0:0[0x205]: Video: mpeg2video (Main), yuv420p(tv), 720x576 
[SAR 64:45 DAR 16:9], max. 15000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
     Stream #0:1[0x2bc](eng): Audio: mp2, 48000 Hz, stereo, s16p, 192 
kb/s
     Stream #0:2[0x245](eng): Subtitle: dvb_teletext
     Stream #0:3[0x901]: Data: dsmcc_b
     Stream #0:4[0x322]: Data: dsmcc_b
Unsupported codec with id 94215 for input stream 2
Unsupported codec with id 1095979811 for input stream 3
Unsupported codec with id 1095979811 for input stream 4

Output for a non affected recording (from ABC News 24 or SBS 2) has 
similar output which I can provide if needed.
Have several samples of affected and non-affected recordings that I can 
share.

Thanks,
Will