Alright, I recently got a new left-handed Schecter C-1 Classic. So far I love the guitar. The pickups, finish, inlay, it's all great. However, I've found one thing that bothers me a little bit.

When I fret a few particular notes on some strings I can hear a faint buzzing sound. The note I'm fretting rings out fine, but there is also a slight buzz audible in the background. At first I thought it was just fret buzz, but upon closer inspection I'm starting to think it might not be. The sound seems to be coming from close to the headstock region. Keep in mind, I'm fretting the note like normal (for example I notice it on the thirteenth fret of the G string), and I'm picking the string between my finger and the bridge, but the buzz seems to come from the area of the string between my finger and the nut.

I've tried changing strings and adjusting the action, but the buzz seems to persist. Luckily, the sound can't be heard when the guitar is plugged into the amp, but I don't always plug it into the amp every time I want to play.

I really can't figure out what it is. I'm starting to think it might be a problem with the nut, but I really have no idea. If anyone has any possible clue what this might be and how to fix it I'd greatly appreciate some help.
The nut might not be cut right, I would take it into a shop and have them take a look. Anyways, I have a Classic as well, congrats! It's a beautiful guitar, both in looks and sound.
My Gear
Schecter C-1 Classic
Fender HM Strat
Mesa/Boogie 1987 Mark III
Peavey Classic Chorus 130
Boss GT-8
Robert Keeley TS9DX Flexi-4X2
its just the strings slightly hiting other frets, its normal and can be fixed with a setup from your local guitar tech.
2009 Engl Powerball 100watt
1985 Marshall 1960a 4x12 with G12-65s
1989 Ibanez 540S LTD DY
2006 Epiphone G-400