one of my tuning keys rattles can somebody tell me wats wrong iv'e tried tighting it but it still rattles help me!!!!!!!!!!!!!!!!!!!
it might be something wrong with the inner gears, if you can take it off (get something to hold it in place so it does fire off, or take the string off first) than you could look to see if there is something wrong with the inner workings and possibly fix it. If you don't wanna do that yourself, i would recommend taking it to a shop and having it looked at.

Ibanez RG7621
Ibanez RG121
How tight is the nut on top of the peghead? Loosen your string on that tuner so it's not pulling on the post and see if the nut spins too easily. If so, tighten it up with a socket.
Moving on.....
thank you i'll end up going to a shop like you told me to if i can't fix it

i'm fixing to buy a martin any way
I hope I'm not suggesting something too simple or obvious... but on each tuning machine there is a small screw on the end that can typically be tightened. When you tighten it with a small screwdriver, such as those used for eyeglasses, you just have to make sure you don't overdo it so that it's hard to turn.

These loosen fairly easily and can rattle if they are not adjusted/tightened properly, depending on the machines/tuners you have.

I hope it's that simple. Best wishes.