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<blockquote data-quote="ziphnor" data-source="post: 178241" data-attributes="member: 14215">That doesnt really fit with my (admittedly limited) knowledge of how DVB broadcasting and DirectShow works. What we are receiving is an MPEG-2/4 transport stream. The data transmitted in this way is equipped with a 'Present' time stamp that informs the decoder when to present the data (and this might be some time into the future) (and similar time stamping is used in the DirectShow filter graph). The decoder should then process and buffer the data (whether audio, video or subtitles etc) until its time to present it. The idea is of course to send data sufficiently in advance to allow all relevant material to be decoded by the decoder. Therefore the exact amount of time spend by an AC3 decoder shouldn't matter, it should just be decoded and buffered until present time.In addition, i would like to add that there might not be one single cause of the sync problem. As mentioned earlier in this thread all the physical AV components in the system (receiver, soundcard, TV etc) can all contribute in a small way to audio/video sync issues. That can then be compounded by software problems.The lip sync issues i have encountered so far in MP are probably related to MediaPortal, or possibly buggy DVB card drivers. Im basing this on the fact that for example starting time-shifting can cause lip sync problems, and that occasional stutter in the image will result in an accumulated lip sync deviation.If you guys want to test this you should try out another program for DVB viewing and see if you suffer similar lip sync issues everywhere.</blockquote>

[QUOTE="ziphnor, post: 178241, member: 14215"] That doesnt really fit with my (admittedly limited) knowledge of how DVB broadcasting and DirectShow works. What we are receiving is an MPEG-2/4 transport stream. The data transmitted in this way is equipped with a 'Present' time stamp that informs the decoder when to present the data (and this might be some time into the future) (and similar time stamping is used in the DirectShow filter graph). The decoder should then process and buffer the data (whether audio, video or subtitles etc) until its time to present it. The idea is of course to send data sufficiently in advance to allow all relevant material to be decoded by the decoder. Therefore the exact amount of time spend by an AC3 decoder shouldn't matter, it should just be decoded and buffered until present time. In addition, i would like to add that there might not be one single cause of the sync problem. As mentioned earlier in this thread all the physical AV components in the system (receiver, soundcard, TV etc) can all contribute in a small way to audio/video sync issues. That can then be compounded by software problems. The lip sync issues i have encountered so far in MP are probably related to MediaPortal, or possibly buggy DVB card drivers. Im basing this on the fact that for example starting time-shifting can cause lip sync problems, and that occasional stutter in the image will result in an accumulated lip sync deviation. If you guys want to test this you should try out another program for DVB viewing and see if you suffer similar lip sync issues everywhere. [/QUOTE]

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