Many thanks for your reply yosemitebill. I now understand but I hadn't realised that the mp3 files became uncompressed in the CDA format (this is the first time I've attempted this sort of thing). Thank you once again.

Older CD players in cars don't play the MP3 format. Check your owners manual for your car.

Sounds like maybe the darker color thing mentioned above may also play into it. My 2001 Grand Cherokee ( factory am/fm/cd/casette player) will not recognize burned CDs. i am currently using my laptop with XP and have tried windows player, I-tunes and BurnerXP but haven't noticed any different results from any of that different software. After going thru about 30 cds burning at different speeds and formats, I finally got it to occasionally recognize one I burnt at around 4X using PCM .wav (uncompressed) format but to recognize and play I usually have to fast forward it thru a couple of songs while it is doing the initial read. Once it recognizes and starts playing then will usually play the whole CD but doesn't always work for whatever reason. I may try the label thing or try to find some of the "dark" cds to see if that matters. We have a 98 KIA witn an aftermarket cd player and it will play just about anything burnt to cd no matter format or speed.

You need to post this somewhere else. Maybe the Electronics Forum? This forum is for those posters that have health problems. Go to the top of this page and look at "Forums" Click on it and select "Home Forums"