Gary’s Blues

I'm really struggling to keep my two draw on my G harmonica from playing flat. It sounds like there's a solid 15 cents between my 2- and 3+. I have sanded my reed plate and gotten a new comb, hoping an improved seal might get me where I need to be, but I'm wondering if I might just have an out of tune reed. What's the ratio for how long you'd fight the intonation with your mouth at six months in vs just installing a new reed plate or buying a new G harmonica? If it's just an experience/technique issue, I'd like to keep after it. If it's an equipment malfunction, I'd like to get better tuned harp asap.