If you have a simple multi-meter or ohm meter, I would check the speaker cable by disconnecting at both ends and making sure that you don't have a short or something else going on. With the cables disconnected at both ends, you should read open or infinity on your meter.

Just another thing to check.

The Rat. M80s, VP-150, QS8s, SVS PC 20-39+, OPPO, Onkyo 703s, Harmony 880 Sony 60" SXRD HDTV