I've searched and couldn't find a clear answer to this.

I own several S9s most are 13.5TH, but I have a 14TH version as well. I have had a couple of hash boards fail and chose to break the seal/void the warranty and send the individual boards off to BitmainWarranty for repair out of pocket and run the miners down a board vs sending the whole units to Bitmain for warranty service (hoping this is the smartest decision financially). BitmainWarranty has now spent almost 2 months attempting repairs with no results or even the ability to tell me if the boards can be fixed...but I digress.

My question is can I run different frequency hash boards in the same miner? If so, am I better off putting the 14TH boards in a 13.5TH unit or can I attempt to put one of the better performing 13.5TH boards in the 14TH unit? Basically I want to consolidate my units so I don't have several units running down a board. If anyone can provide their experience with this or what my best course of action is it would be much appreciated!