The Sony 9000ES offically doesn't support CDR's.
As a recommendation, I found that one brand of CDRs if recorded at at 1X speed can be played on the 9000. I now don't remember the brand, but it wasn't Sony. I haven't tried to play a CDR on my 9000 for over 18 months. I just assume that it won't.
I love my 9000ES, but if you want to play CDRs, get another player.