You are covered in the Sale of Goos Act. You go back to the seller and remind him of this. Your can demand your money back or a replacement for up to 6 years after the purchase if the goods are not fit for purpose - you have to prove that, which won't be a problem.
The seller is playing silly ******* with you and trying to wriggle out of it. Do some googling on the Sale of Goods Act and you will see exactly what you're entitled to.
Your year's warranty means ****** all because you're covered anyway. I never take out a warranty when I buy stuff like this, if something happens to it to deem it not fit for purpose then I know I'm covered. I had jumped up little so and so try to tell me that I *had* to take the extra warranty out when I bought my plasma TV, I told him I didn't want it, he asked why, I told him I'm covered under the Act and he said "oh, but that doesn't cover accidental damage", I said "I know, that's why I have home insurance!!"