CD-R did the trick. I now can play the burned audio CD's.
BTW, the burner is an Optiarc DVD RW AD-7200S and the discs are Memorex. It looks like it is a good combination but burning at 48X caused some jitter in parts of the recording. 8X worked well, though. Quality, not quantity.
It's good to hear my old JVC play my burned audio discs.
Thanks for all your suggestions.