Strange Problem

I set 2 programmes to record and started to watch the first about half an hour in whilst it was still recording. This seems to have caused the second recording, which started whilst I was watching the first, to have become corrupted as the sound seems to skip all the time. This is the second time this problem has occurred. I hope I have worded the problem so that it is understandable, as I have had to read over it twice myself lol.;)