Ok, I'm going to ask this again. Why are you putting a 3/8" layer of plywood down over the 3/4" T&G plywood.
I thought you were using Schluter Ditra on the floor?

Direct bonding to plywood is not a good idea. At the very least you should be using an approved tile underlayment type backer board installed per the manufacturers guidelines.

As for the shower floor, you only need the 3/4" plywood subfloor to install the mud pan over.

Unless your installing a natural stone type floor then the 3/4" T&G plywood is fine, but you still need a proper tile underlayment layer to bond to.