I took it for another test drive today. When it works, it works well, when it doesn't it sucks.

I drove from Reigate to Hook (30 miles or so) and it only managed to lock onto the BBC national MUX for about 5% of the time.

So I need to look at improving the aerial to see if that helps. You say it got worse when you extended it ?

I was looking at either extending it, or fitting a proper DAB aerial.

I know nothing much about aerials. The aerial is just a single wire, I'm guessing that a proper DAB aerial has two connections, antenna and ground ??? If so I guess I have to find somewhere to connect the ground to ???