Receiver shuts down at moderate volume level (When connected to R input of Sub)

[Skeletron]

Hello! I'm troubleshooting a problem I'm having with my Polk PSW10 subwoofer and I'm wondering if there's anything I can do to fix it.

The signal chain is:

Sherwood RX4109 receiver -> Polk PSW10 L/R speaker level inputs -> Polk PSW10 speaker level outputs to speakers

Earlier today, a technologically challenged family member set the receiver's volume to maximum while listening to a Youtube video with the volume set extremely low. Then, opening a video on Facebook with the volume set extremely high, the subwoofer/speakers were blasted with an enormous signal. After that, the receiver began to shutdown at moderate volume levels.

When I got home, I narrowed the problem down to the Right Speaker Level Input of the subwoofer. When speaker wire is connected between any output of the receiver to the the Right Speaker Level Input of the Subwoofer, no audio can be heard from the subwoofer but if the volume is turned up past a moderate level the receiver clicks off.

I tried connecting the speakers directly to the receiver and they still work fine. The left speaker level input of the subwoofer also produces sound and seems to be working fine.

Does anyone know what could be happening here? I'm assuming the loud volume surge shorted something in the right speaker level input of the subwoofer but I have no idea. If I open the subwoofer would I be able to see physical evidence like a fried board or something?

Thanks!

 

[sdifox]

Just use the left speaker level input. Right one is toast. You definitely have a short on the right speaker level input. Visual inspection probably will point you to the general direction of the problem, but a multi meter and know how are what you need to fix it.

 

[Number1]

Consider yourself lucky the sub is still useable. Open it up and have a look around. The failed component should be close to the high level input terminal but there might not be any visible signs of failure. Post pics if you find something.

Edit, there is a risk of frying your amp with that blown input if you try to use it again so it might be a good idea to internally disconnect it. Just cut the wire and tape it with electrical tape.

 

[Skeletron]

Right on. For now I just have three outputs on the receiver going to the speakers and L speaker-level input of the subwoofer (instead of receiver -> subwoofer -> speakers like before). It's fine. I'll probably open the subwoofer and take a look around one of these days though.