Hi Geoff, DAB reception issues are a known problem and I experienced the same with my car from new (6m old). I have just recently had the Dealer Update done and it has massively improved the issue - perhaps totally resolved it (will know the more I travel). As far as I know, you cannot conduct this update via DIY/USB Stick. Even if possible, I'd worry about Warranty Implications from tampering with vehicle software - not worth the risk when the Update is Free!
