Most cd burner programs will convert the mp3's to normal cd audio format. You need to select audio cd format in your burner program & not mp3 disk. Also, I would highly recommend you burn your audio disks at minimum possible speed. Some car & other cd players don't like cd-r's burnt at high speeds. Make sure you use reliable brand blank cd-r media. See
Burning an audio CD from your MP3's (which is in a Sticky at the top of this section!) lol