Thanks for the reply.

I have tried a few things, including leaving it disconnected for quite some time.

I have sent Brent an email and am waiting for a reply.

I was sorta hoping someone may have some other ideas, but I feel I may need a new sub or at least a new amp.
Not being electrically minded in the slightest and depending on how hard it is to install a new amp, I may need to purchase a new sub.

It just annoys me that my nice big EP500 has died and that my old Sound Dynamics sub is still going after approx 10 years.