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Hey guys,

It's my first post in this forum right now and I am having some serious trouble with my HD PVR. I've read the froums here for a long time when I first got my HD PVR to get into recording using Linux but now I came to an issue I could not find an answer for.

Maybe this problem is known, logical and already desribed here - if so I could not find the proper thread for it. So Sorry in advance.

Okay here's the thing:

I made my first records with the HD PVR with consoles (PS2, PS3, Wii) connected via Component cables. When I first got the device I did recording on all of them and I also decided to test for two things:

1) Long time recording to see if recording "breaks" at some point - as the HD PVR seems to be prone to overheating

2) Long time recording as I am ALWAYS suspicious of increasing AV sync trouble when recording anything over a longer period of time.

However all devices connected via component run just fine.

Now I was calmed down and happy with the success I now tried to record around an hour of N64 footage done via Composite input (so I am using the front connectors). And I got what I expected:

a) After 5 minutes, a drift in AV sync is noticable. I suspect it being around 1 second after 20 minutes of recording - the Audio is "behind" the video - so it comes later than it should - or maybe: the Video is too fast.

To isolate the problems, I connected an Atari 2600 I added an S-Video mod to. HERE however it seems the Audio is ahead - means Audio too fast or Video too SLOW. So the exact opposite of what I get with the N64.

Maybe of notice: I am using PAL devices. The video also shows a 50FPS - which seem to match what PAL is supposed to produce. So I guess this problem isn't produced by some "device thinks it's NTSC but it isn't" or any similar problem. Even tho I think it's the Video that is somewhat faulty due to the different issues with the N64 and Atari.

b) I noticed on a ~40 minute mark the Audio starts behaving strange (again - Composite, only - this test was done with the N64). Sound slike the Audio "shutters" and I can hear some bleeps (like a Slow motion R2D2) during the recording.

I usually grab my footage via "dd" on Linux. And I also tested around with the ShowBiz Software that comes with Windows. All variations to show the exact same problems as decribed above.

Now I usually would be fine with the Sync issues if I could find SOME way to estimate the exact drift value - that way I could fix the issue while deinterlacing I always do before working with the footage. But while the drift seems to be constant with N64, it's totally different on the Atari - and I suspect other devices have different drifts as well. Also the Audio shutters are pretty annoying - especially when I want to record over longer periods of time.

I haven't tested that one, yet but in worst case I just gotta pipe the PVR output to VLC or mplayer and just screengrab it... I cannot see why the issue should be present when playing back the PVR output and so far screengrabs have shown immune to problems like this on my end.

So if anyone if able to give me some advice on how to proceed, tackle this issue I would be very happy. Even if someone just knows the technical side of this problem - without having a possible solution - so I could *understand* what's wrong - that would be very helpful, too.

Thank you.

- Christian
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