RX300 Spur

The only gripe I have with the SE is the Sound System - the standard system is very 'tinny'. Any idea if you can upgrade? Or if I put in my own, would it invalidate the warranty> Cheers

Hi All Pleased to say I have joined the RX300 SE Club (March 05 plate). Must say the SAT NAV with bluetooth is a great gadget! I PXed my 525d and donot regret it for one minute. I was also very impressed with the Lexus customer service compared to BMW. Just a quick question, does/has anyone put Running Boards onto their RX? Any ideas in terms of where and how much this would cost? Thanks