Pioneer CD-Writer for Stereo-System

I apologise if this is the wrong forum to ask this question as this is my first post on this site.
A friend of mine has purchased a Pioneer PDR-W739 CDR for his stereo system. It will not accept cheap CDR's.
Is there a way around this, e.g. an hack. Or failing that is there a way to format cheap CDR's to make them the same as the music-only ones.
Or where is the best place in England to purchase music-only CDR's if all else fails.
Many thanks, Wint.