Rubber idea reminds me of building a floating floor. I agree that it *should* help. How much, I don't know since you are still screwing the drywall into the joists through the rubber in a number of places. Not saying that it will hurt anything, and the benefit might be better than direct connection to the joists, but you may want to look at something with more than a 12" spacing. Just my thoughts. I have no professional expertise with that at all, but just basing it off of my conversation with John from The Sound Proofing Company.


Farewell - June 4, 2020