Quote by FRDesign
My Locking Nut keeps making creaking noises on my Ibanez whenever I use the trem.

And then it comes up sharp or flat!

Have you tried tightening it a little better?

Other than that, check if the trem is setup correctly and if that is the case, and the locking nut is super tight I'm affraid you could be looking at a trem replacement or at least blocking.
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Hmmm, ibanez RG350. My mate has an RG 370 and it does the same. Can't help you but it looks to me like its something to do with the parts used on those RG's
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