right im gonna be really breif,
I have an ibanez and its not that old, its in brilliant condition appart from the fact that when i tune my guitar ( drop tunings ) my what would be the G string wont tune perfectly and is slightly out of tune, no matter what even when turning the tuning peg it won't tune into the perfect key.

fellow rockers (: what the hell do i do ?
New nut, if that doesn't solve it new tuners.
Or you could buy different strings with a wound G string, that would solve it too.
lubricating the contact points between the guitar and string could help to some degree, also new nut/tuners could fix it if yours are really bad.
Did you set the intonation? Tune the strings to pitch like you want them, now fret the string at the 12th fret. Using a tuner, is the string at the 12th fret the same as the open string? If not you need to adjust the intonation

4 Custom Strats
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1 Custom Telecaster (Warmoth)
2007 Jimmie Vaughan Sig Strat

Callaham Hardware & Bridges
Fender Custom Shop 69's
Dimarzio Breed Pickups

Blues Junior Amp
BlackStar HT Club 40 Amp
I have always had good luck with Grover tuners, I would recommend them.
Epiphone Les Paul Custom AP (w/ 2 Seymour Duncans)
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Epihpone Hummingbird

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