Is it the hybrid or series mode type of protector? Or the kind that eventually get "used up"?
I'm not sure of the difference, I guess, but I don't think it is one that is something that gets "used up".
I decided to call Panamax. According to them, they should last forever absent damage or severe lightning strike. They do have lifetime warranties for damage to equipment, for whatever that is worth. I don't know how you would even know if it had been damaged without opening it up.
I started thinking about this because my system has a bit of a low level hum and I thought the Panamax as a line conditioner was supposed to help with that. Anyway, I removed it from the equation and there was no difference, so at least I know it's not the problem, although I don't know if a replacement would help.