Thanks for the replies.

Yes, we still receive analogue in the UK. I didn't realise the tuner was both analogue and digital hence my picture breakup must be happening when it can't get a digital signal and it's tuned to an analogue station.

I can't get DAB with the car anywhere in South East England although my portable DAB radio in the house works fine. There must be a problem with the DAB unit or aerial connection, etc.

Cheers
Nick