Audio lip sync issues on my DVD Player
I just bought a Panasonic DVD-S68 upconverting player recently, and whist the picture looks good upscaled on my HD TV, I've noticed that the lip sync is not matching up with the picture. For example I was watching a movie via USB on the player last night and I noticed this issue, but I just assumed it was the actual movie torrent file that was the problem, because some torrents are just duds. The audio was about half a second quicker then the video and its very frustrating to watch. I then hit pause and then the play button again and the lip sync was back on track like normal but the problem kept re-occurring every 3 or so minutes. Now I'm watching an actual disc on the player and I'm getting the same inconsistency with the audio. Its the same exact same case too in that whenever I hit the pause button then the play button immediately after, the lip sync will play normal for a few minutes before playing up again. Obviously I use HDMI.
Also, I don't have this problem with my DVD/VCR combo player via RCA cables, that is also connected to the same TV.
So what could it be and can anyone give me some advice to how I can resolve this annoying problem? Could it be the specific HDMI cable that I am using? Is it the player itself? Are there options I could tweak to fix the problem?
I would appreciate help guys, thanks