G'day,
Edited: Just noted you mentioned soundhole. Scratch electric.
What kind of guitar is it you are having problems with? Acoustic Dreadnought? Shape, balance, size and bulk matter.
Dreadnoughts are a personal physical size/fit thing. Their body bulk is just too uncomfortably big for me seated. My preferred solution is to avoid them. When I do play my Dread, I play standing, with a strap obviously.
edited