Random Stereo Problem

[threestacks]

The past few times I have taken the car out my CD / Radio player seems to be playing silly buggers.

It turns on fine at the beginning and plays music for a while but the it switches off and it as if there is no more power going to it. Won't be able to switch it on at all, not even a standby signal, for the rest of the day. Park up, leave it a day or two and the its works again, for a short while.

Could it be a dodgy fuse or relay?

Any ideas out there would be most welcome :-)