Um I dont know who told you it would blow up or whatever that's just not true lol! What you can do is get phono to 3.5mm cables and connect the 5.1 (6xphono) pre-outs on the av receiver to the 5.1 input (3x3.5mm) on the z5500. Or you could connect the optical/coaxial output of the receiver (if it has one) to the corresponding input on the Z5500. It should work fine and should sound great. I dont know how an av receiver would help you in your situation though, as most av receivers only have one set of analogue 5.1 inputs, so only one PC could connect to the AV receiver by analogue 5.1. You could use digital but then you might as well use the digital inputs on the Z5500: one PC connected by 3x3.5mm 5.1 analogue, one by digital coaxial, and one by optical coaxial. There is even a 3.5mm spare on the side for any other stereo analogue devices/pc's.