I have an Audi chorus cd changer/cassette head unit. Outside of town, picks up strong signal radio stations ok, albeit a bit fuzzy. As soon as I head into town, the signal just drops completely. This is on radio stations radio 1 and radio 2. Would it be a problem with my aerial, or connector into headunit, or something else? I live in Milton Keynes if that helps. Not really crawling with sky scrapers blocking signal lol.