Infinity Oreus Subwoofer Problems

Hi

I have a problem with my Infinity Oreus subwoofer

It has started to make a sound like you would hear if a FM radio was not tuned in correctly but the noise pulses

This shappens whether there are any cables form the amp connected or not

I foumd some ref to this on Google from 2009 but no answers

any help would be greatly appreciated

Thanks, The Dodge