concert head unit problems

[s4mark]

Hi all.
My b5 S4 concert headunit keeps on playing up. One minute it is fine, but sometimes when I start the car, the stero lights up, but no buttons work and there is nothing displayed on the screen, just dead. Seems to work again if you leave it for a couple of hours.

I thought it might be the power lead loose but it doesnt go into safe mode and still lights up. Any ideas appreciated.

Thanks

 

[macattax]

I had a similar problem but it turned out my son had put a coin into the cassete player. The coin would short circuit the stereo each time I went over a bump. If you can remove the stereo and give it a shake and listen for any rattles. If you hear rattles something is in there perhaps a coin.