Listening to the radio earlier and put the heated window on. The radio lost its tuning and went all noisy. Turned the heated window off and all was well again. Is there a fix for this or is it normal on the Superb?

Provided that you have saloon then I believe the rear window has both heating elements and radio antenna integrated into it.

 

Its not normal to have interference when you put the heating/demister on but it can happen if one of the elements on the glass has a has a break. 

 

If that is the case, there is a conductive paint that can be used to bridge the break and restore the connection (did this to a buddies Audi where someone had scraped off a dealer sticker and cut one of the elements).

Edited 2 November, 20169 yr by TheRobinK

Having similar trouble when using the 12v socket. Hmm

Try plugging something else into the socket and see if the noise disappears. I'd blame the appliance rather than the car wiring first - especially if you're using an inverter or a something with a cheap commutated motor.