Home / Forums / General melodica discussion / P-37D wildly out of tune? Also: delayed key sound. / Reply To: P-37D wildly out of tune? Also: delayed key sound. Reply To: P-37D wildly out of tune? Also: delayed key sound. February 16, 2022 at 3:48 am #14037 André Sant’AnnaParticipant This is awesome, Barbara. I will certainly give it a try. You know, I’m trying to tuning the reeds with nail polish with good results, but I can’t recommend it to other people because I don’t know if it can eventually cause any damage to health since it’s a product considered toxic (although I use an organic nail polish, which is less toxic). Anyway, when I use it on the base of the reed, to flatten the pitch, it doesn’t work! Are there any tricks about this procedure?