I bought the Yamaha HTR-5560 yesterday. The thing that annoys is the 6.1 matrix. I think I really want the descrete 6.1 that's on the HTR-5660. Always bugs me when the reciever is not reproducing what's on the dvd. Is there any other differences between the HTR-5560 and HTR 5660. I'm looking at about an extra $100 if I return mine for the HTR-5660.