Mp3 playback

Hi Chaps I have an 08 Octavia withe the standard Stream Mp3 head unit,I mainly use the stereo to play back radio podcasts from cd some of which are up to an hour long, my problem is sometimes when I leave the car and then restart the podcast goes back to the start which is a total pain, and other times it re-starts at the last place just fine,is there anything I can do to stop it happening apart from buying a new head unit? Thanks.