I have the same problem. Using the radio in 1:10 TC Electric.
Tried the Spektrum cap but did not help.
It was so bad at the race last weekend that I had to go back to my old 3PK with Spektrum module.
Believe my radio is from the first batch (was the first Tower handed out early July)...but did not use it before now...
Waiting for a reply from Futaba support....
Tamiya TRF, Sanwa M12, SpeedPassion, Much More, LRP