I have a Yamaha RX-V567 avr and Polk monitor 70s series II and the speakers sound OK but I feel like they can sound better I just don't know how. It doesn't sound as clean or crisp as i'd like them to sound. Could it be the receiver? Or do these speakers sound a little muffled or muddy no matter which receiver or amp is being used? Blu rays, directv, video games all sound similar to me. Any way to improve the clarity of these speakers would be awesome even if its just a little bit. Any ideas or recommendations? Thanks!!