Log says all:

2008-09-17 18:36:43.489000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=H264 resolution=3232x24672 aspect ratio=16:9 bitrate=15000000 isInterlaced=False
2008-09-17 18:36:43.607000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=MPEG2 resolution=720x576 aspect ratio=16:9 bitrate=5000000 isInterlaced=False
2008-09-17 18:37:01.045000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=H264 resolution=560640016x2720 aspect ratio=16:9 bitrate=15000000 isInterlaced=False
2008-09-17 18:37:01.413000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=MPEG2 resolution=720x576 aspect ratio=16:9 bitrate=5000000 isInterlaced=False
2008-09-17 18:37:03.446000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=H264 resolution=480x320 aspect ratio=16:9 bitrate=15000000 isInterlaced=False
2008-09-17 18:37:03.609000 [Info.][3]: TsReaderPlayer: OnVideoFormatChanged - streamtype=MPEG2 resolution=720x576 aspect ratio=16:9 bitrate=5000000 isInterlaced=False


h4. Steps to Reproduce
Hard to say. At least here all analog channels show this behaviour.
Other users reported this issue using DVB-C.


h4. Additional Information
http://forum.team-mediaportal.com/developers-lounge-70/tsreader-dynamic-content-detection-45273