shock from AV Adapter for iPad

Ive had a mild electric shock from apples AV Adapter for iPad, and can see it has developed a split in the rubber casing, which has blown out at one end. Ive tried to talk to apple about this, but had no real responce so far. Ive had it for about 15 months now, so I dont supose they will replace it even though it started acting up and overheating some months back, but was told thats normal. I rreally think a so called high quality product (priced £35) should last longer and more importantly be safe. Whatever happens I wont be using it again. Has anyone else had any problems with this item ?