Phil, Yes, I'm using the strings that came with the guitar. They are 10's. And it is supposed to be a graphite nut, I believe.
Guess I'll contact the support center and see what they can do.
I have a new JTV-69 US and the high E string occasionally pops off the nut when I'm playing.....never had that happen to any guitar I've owned and I have some very nice Fenders, Gibsons and PRS guitars. I'm a little disappointed after spending $3900 for this. It doesn't do it all the time and I really hate to go through the hassle of sending it back if I don't have to. How hard would it be to adjust the nut so it doesn't do this?