How old are the speakers? Able to try another pair of speakers? Check across the speaker terminals for even the finest strand of wire touching across terminals on both speaker end and amp end. I would borrow a small pair of speakers with a benign load if you don't have a pair handy. That problem screams short somewhere , speaker , wire hopefully something easy to troubleshoot and repair
If you have a volt meter you can find the static impedance for the drivers in Klipsch speakers if so inclined you can measure across each driver to make sure you don't have a bad voice coil. If its the speaker's they are easy and cheap to fix
Good luck