an annoying buzz

francour

My all polk 7.2 system is almost perfect. 1 sub (Split out of 1 output) has a very soft hum. It does this regardless of being hooked up, even when the power switch is off. I have replaced the driver, but no change. Any ideas? It is only 1 of the subs that does this.

r.camacho1

I had the same problem at work, it was a result of the subwoofer cable having a loose connection. Try a different cable, that might work. Other than that, I'm not to sure what else would cause it.

francour

Thanks for the advise. Unfortunately the sub hums even when no sub cable is connected.

AsSiMiLaTeD

So the sub hums when no cable is hooked up and when it's turned off?

francour

yup. if the sub is plugged in (any outlet) it hums, whether it is switched on or off.

AsSiMiLaTeD

IS it a Polk sub, which model?

r.camacho1

The only other thing that I can think of is that your amp might be going out. In that case, if you still have a warrenty on it, have it fix. If not, it might be time to buy a new one. Sorry that I couldn't provide more help.

francour

the model is psw303

francour

the model is psw303...

dpowell

Is the sub grounded? I had some humming problems with the sub in my CS1000 center channel. At the advice of Polk tech support, I added a converter on the end of the cable to convert from 3-prong to 2-prong (no ground). Problem solved!

If that doesn't work, you also might try a ground-loop isolator, especially if you have cable TV. That can introduce interference into the line.

francour

thanks for the advice... i will try both steps and post the results in the next day or two.