Well, I did some reading on Arnie's. Here:

http://www.arniesairsoft.co.uk/forum...24&hl=selector

Second last post, the guy says he fixed it by pushing the two copper contacts up a little. They get pushed down after a while and don't make proper contact. I just tried it out, and it fixed Sharpe's AK no problem.

Yeah thanks everyone who tried to help... i knew it would end up being something stupidly simple :P

so its all fixed then? good for you dude... well good for your buddy whos buying it i guess