CD READ PROBLEM with VDO DAYTON MS5000 (by 3 users)

Hi,
(don't know if this is the right place to post)

I have a VDO Dayton GSP Navigation system (MS-5000) for a coupld of months. Works perfectly.
But since the freezing cold, it has problems reading the CD. The computer is located in the car trunk.

After riding a coupld of minutes, the CD was taken back in the computer and the system could read it.
since 2 days now, it does not read any cd anymore.
But the system still works, I have the menu on the display and so on and I hear the laser trying to read the cd. But after 5 seconds it is
trown out and it takes it back in after 10 second and so on and so on.

My questions are :

did someone had this before ?
is it the lens that might be dirty ?
Is there a good cd that exists to clean it (I have tried a cleaning cd with 4 brushes, but that did not help at all ?
It is only 4 to 5 months old...what could be wrong ?

Any experiences ?

Regards,
Stefaan

Please email a copy to :

Thanks a lot friends