Absolutely the first thing to check. Make sure that the connections are clean at both the speaker end of the cable and the receiver end of the cable. Make sure there are no stray strands that are free to make contact with other wires.

Second, make sure your receiver has enough ventilation. Any place that there is a set of holes on the receiver needs at least 2-3 inches of clearance for ventilation. Do not cover or block these holes or else the receiver may overheat and shut down.

Let me know if either of these suggestions help.

Jeff