Infinity Kappa 8's

What to do? My infinity Kappa 8's keeps eating amps for lunch.The 1st failure was with a Yamaha 200 watt per channel model P2200. Amp went black, I replaced the main fuses on the back of amp, it powered-up with new same rating fuses and then amp died again for good.Tryed another P2200 fuse blew again. I've decided not to try the amp again, for fear of completely damaging my last P2200. This is getting expensive! I'm not cranking the volume at full tilt or pushing the bass tone control past 12 o'clock. The speaker can be Bi-amped, but I've just used a single robust P2200 on them. The speaker wire uses large 1/4 inch bananna connectors, so no bare wires can not touch positive to ground on the back of the amp or speakers and the 4 binding posts on the speakers flat metal plates to connect the two binding posts together for single amp operation. Could a faulty cross-over wreak this havoc upon me. Any helpful suggestions will be greatly appreciated.