Your car/rack players do not play wma, wav or mp3 audio file formats - the
only ones available when burning with WMP.
You might get around by copying straight from audio CDs to writable CDs -
i.e., rip/burn in cda audio file format. You cannot save in .cda format.
Look for wma, wav, mp3 to cda converters (software) on the web.
Otherwise, buy newer players that can open the wma etc files.
Michael