Philips DVDR70 and DVDR80 synchronizing

I have read that some people have had problems with the synchronizing of
the sound and picture by using the Philips DVDR70 and DVDR80 as a
TV-tuner. The picture got a little delayed from the sound. And the
problem was the same by playing DVD's that was recorded on these
recorders. By playing ordinary DVD-records bought in a shop, this error
did not appear. Is this a known problem with all of these recorders, or
what?

Peter.

Peter