The NEC code requires class 2, and in some cases allows class 3, wiring for in-wall purposes. What is the danger (e.g., fire hazard, etc.) of using a non-rated speaker wire with PVC jacketing for short (e.g., 4') in-wall runs. In particular, I want to use Radio Shack Megacable 14-Gauge Flat Speaker Wire to run from the baseboard, behind the drywall, up 4' to my surround speakers on the wall. Here are the specs for this wire: Specs. Problems?