Bigbsy Trem Problem

Hi Guys,

I just parted with my hard earned and bought a Gretsch Electromatic Duo Jet with Bigsby (Damm thats a mouthful and a half).

Anyone the bigsby is causing me some problems with regards to tuning. The slightest touch on the bigsby (up or down) and all the string lose their pitch by almost a full step.

Now I'm pretty sure the problems up at the nut or pegs because the bigsby is pretty simple (besides the bridge there isn't anything for the string to really catch on).

Another forum suggested rubbing some pencil lead into the groves in the nut to help stop the strings catching but this hasn't helped much.

I'm thinking that the tuning pegs are at fault because they seem to have a bit of variance in them. By that I mean when I'm tuning up to pitch it takes a different amount of turning each time. With my previous guitar the amount I had to turn the peg seemed to be fairly constant.

So has anyone got any ideas how I can narrow down the problem? And any suggestions as to how to fix or improve it would be appreciated.

I'd like to put a locking nut on the guitar but I'm not sure if its possible? Also what about using locking tuning pegs - can someone explain how they help and if they'd work?

Thanks,