I just bought a used qsc mx1500a over ebay. No I go to hook it up and plug my Eden Navigator into channel 1 of them amp, and send the powered signal, out through channel 1 via a banana plugto 1/4" cable to my cabinet.No sound whatsoever. I then realize that the amp is not detecting any input signal. I am using a "guitar' patch cable to run from my navigator into the RTS inputs...is this the problem? I want to make sure this amp works, and I think it probably does, I am just not hooking something up right...Yes I already RTFM, and I just can't figure out what I might be doing wrong... ps..I figure qsc tech support is not open till monday and that is why I am posting this here. Also I have tried a multitude of patch cables on the input stage, and the banana to 1/4 " speaker cable is brand new.