The RC battery drain was happening without any phone or tablet device connected, just pairing the RC and the MM would cause the RC battery to drain quickly, as demonstrated in the YT video I posted above.
In my case I was able to recover from the issue by totally draining the RC battery until it would no longer power on, then recharging using the smart charging port from the MM battery charging hub. I had to repeat this process a couple times and now my RC fully recharges and no longer indicates any unusually fast draining. The early symptoms of the RC battery drain issue was that the RC would stop recharging at about 75%, showing only three LEDs when the battery test was done or when the RC was powered on.
It’s possible that the new 1.0.5 RC firmware fixed the cause of the drain issue, but time will tell. I can say that in my case I no longer see the issue.
I believe this was a firmware bug, which was incorrectly reporting the battery charge level, like a bad fuel gauge.
Completely draining and recharging the RC seems to recalibrate the RC smart charging firmware.