When I'm watching a DVD and I fast forward or change chapter,my front speakers make a bang or a hard thud sound. I have a Philips DVDR890. My fronts are Diamond 9.5's (30-24khz) and I have the crossover on my receiver (Yamaha RXV-650) set at 80hz. This is not heard in my subwoofer or surround speakers and only happens while "fast forwarding" or "re-winding" the DVD's. Any ideas? Thanks.