Hi all, hope I'm posting this in the right place. I have an Audi A4 TDI Avant, 15 plate. Great car so far but I'm not hugely impressed with the stereo. I assume it's just the standard system, not Bose or anything. My question is, can the system be upgraded? Is it just a matter of new speakers or do I need to do more? And any recommendations for decent hi-fi people who could do it? I'm in the Cheshire / South Manchester area. Thanks in advance!