Dishwasher Mains Suppressor Blows Fuses?

Hello,

My Hotpoint FDM550 dishwasher kept blowing its plug fuse at random intervals. I traced it to blackening on the mains suppressor which I replaced.

All was ok for two weeks but now the fuse is blowing again. The suppressor is now blackened like the old one. When I change the fuse and plug it in with the machine lying down so I can see inside, there is sparking in the suppressor as if it's shorting out although I can't see any obvious leaks where moisture is getting in. Could I have got two faulty suppressors on the trot?

Any thoughts would be much appreciated before I scrap it for a new machine.

Cheers,
Mike.