Samsung DVD HR-753 Recorder sync



Hi all
I have a problem.
When I record from my digital tv set top box
The picture is out of synchronization with the sound.
I previously successfully changed my region code from region 4 to all.
but now this sync. problem is there.
any help would be appreciated
because I am a bit deaf and I find it very hard to understand what I have recorded. ( I might add that when I record analoug from within the recorder, it is ok)
Thanks for any help