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<blockquote data-quote="davidf" data-source="post: 1020257" data-attributes="member: 19484">If you are referring to the Hw vs System then this number is expected to drift and wander.&nbsp; The value represents the difference between the clock on your motherboard and the clock in the audio hardware.&nbsp; MPAR uses the audio hardware to determine the media time rather than the motherboard, as the when the audio hardware has produced 10 seconds of sound then 10 seconds of media have passed (no matter if your motherboard says different - to use it would cause periods of silence (motherboard clock slower than audio hardware) or missing audio (motherboard faster than audio hardware)).&nbsp; On some setups one or both of these clocks can &quot;estimate&quot; some values - on Xonar hardware we've seen the clock go backward on occasion.&nbsp;For your purposes the drift is the one to watch - it's how much difference there is between what you see and what you hear i.e. how far ahead the video is from the audio.&nbsp; For situations where little resampling is required it is better to pass the audio to the hardware as it is on the TV broadcast and only resample the audio when the difference between what you are seeing and hearing gets to a certain threshold (18 ms from memory).&nbsp; This is done as resampling degrades the audio slightly and you will only notice the &quot;drift&quot; when it gets to about 20ms or above (substantially above usually).&nbsp;It is possible for MPAR to be out of sync (starts out of sync and stays out - very rare and I can't find the cause or replicate on demand), but if it starts in sync it should stay there.&nbsp;The reason you should not use MPAR with live TV is that your TV provider will only provide TV at a certain speed (50Hz) so if MPAR resamples the audio to match the refresh rate of your TV then you will run out of buffered TV broadcast to display - at this point any one of a number of bad things might happen, usually stuttering or silence followed by picture breakup (occasionally Live TV stops as it thinks the stream has stopped).&nbsp; This would be true in your case as your monitor/tv is running at just over 50Hz so MPAR will resample so that: just over 1 second of stream audio is played in every second of real time.&nbsp; While this will cause you to have a nice smooth picture it will not last for long enough for an evening of TV viewing.</blockquote>

[QUOTE="davidf, post: 1020257, member: 19484"] If you are referring to the Hw vs System then this number is expected to drift and wander. The value represents the difference between the clock on your motherboard and the clock in the audio hardware. MPAR uses the audio hardware to determine the media time rather than the motherboard, as the when the audio hardware has produced 10 seconds of sound then 10 seconds of media have passed (no matter if your motherboard says different - to use it would cause periods of silence (motherboard clock slower than audio hardware) or missing audio (motherboard faster than audio hardware)). On some setups one or both of these clocks can "estimate" some values - on Xonar hardware we've seen the clock go backward on occasion. For your purposes the drift is the one to watch - it's how much difference there is between what you see and what you hear i.e. how far ahead the video is from the audio. For situations where little resampling is required it is better to pass the audio to the hardware as it is on the TV broadcast and only resample the audio when the difference between what you are seeing and hearing gets to a certain threshold (18 ms from memory). This is done as resampling degrades the audio slightly and you will only notice the "drift" when it gets to about 20ms or above (substantially above usually). It is possible for MPAR to be out of sync (starts out of sync and stays out - very rare and I can't find the cause or replicate on demand), but if it starts in sync it should stay there. The reason you should not use MPAR with live TV is that your TV provider will only provide TV at a certain speed (50Hz) so if MPAR resamples the audio to match the refresh rate of your TV then you will run out of buffered TV broadcast to display - at this point any one of a number of bad things might happen, usually stuttering or silence followed by picture breakup (occasionally Live TV stops as it thinks the stream has stopped). This would be true in your case as your monitor/tv is running at just over 50Hz so MPAR will resample so that: just over 1 second of stream audio is played in every second of real time. While this will cause you to have a nice smooth picture it will not last for long enough for an evening of TV viewing. [/QUOTE]

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