Not a media issue? Have you scanned one of these media after burning?
The problem is either
a) Exists with the original
b) Introduced while transcoding
c) Introduced while burning.
d) Poor quality player.
My bets on either C or D, with a heavy bios towards C.
You have not told us anything about your media, your source, the programs you've used, your burner or firmware, nor anything else.
Please post a nero infotool log (with any serial numbers removed), a CD/DVDspeed quality scan, or some info on what you are actually doing and the programs (and versions) used.