Gin and Chronic

Hey All, I'm having a similar issue as the OP, and am hoping to capture your thoughts. The model I own is the R-115SW, purchased a few years back. We recently moved, whereas this issue did not exist in my previous home. Once moved, the subwoofer operated normally at lower volumes. The second I get it right volume for movies (same as previous home), it shuts off automatically, and I have to go unplug it, and plug back in to get it to go on. For full transparency, I lost the OEM power cable in the move, and the new one is three prong (female), with a loose fit. I ordered a replacement that called out the R-115SW in the listing detail, but it's the same female 3 prong, and a smaller gauge than I recall from OEM...same issue occurs. I have messed with the frequencies, the phase, the gains across both the receiver and the sub to the same end. It seems this may likely be a bad amp in the sub, but really looking to figure out how to confirm that prior to spending the $$ on a new one, as I'm likely out of warranty. Any help to troubleshoot, or support in getting necessary replacement parts is greatly appreciated.