Settin up sl1200?

I have tried every possible remedy i can think of to set up 1 of my decks but i cant get my stylus to stay in the groove wen i handle it.Tried new/old styli,shifted the cartridge up an down the head shell,added extra weight to the end of tone arm,tried it with arm lok on/off in fact tried just about everyting i can apart from sticking a coin on the headshell(i know wot damage that it causes)any ideas?