SOLVED, bad string! Is this tuning issue nut related? PRS DGT Wood Library

^^^ This was it! I pulled the string last night and immediately noticed there was a slight bend in it right over the nut slot.

Installed new strings all around, stretched them, and we are staying in tune now.

I’m still hearing a slight pop every now and then so I’ll take a few passes with 1000 grit sand paper at the back of all the slots.

Thanks all for your help! Glad the bone nut will work. I like the look of it over the synthetic black.
Glad to hear you got it sorted out