New firmware FT-991 08/24/16 - possible problem

Since updating to the 8/24/16 firmware, I've now had several instances
where pushing the radio front power button will not turn on the radio.

Disconnecting then reconnecting the DC supply corrects things, then the
radio will turn on with power button as normal. This problem would probably
not happen if my radio were not connected to constant DC power, since
cycling the DC power resets whatever is getting stuck/confused.

I've now performed a reset, repeated the Main, DSP, and TFT updates,
including by another reset, then restoring my settings with the RT
systems software. I will see whether the problem continues.

Has anyone else experienced this non-responsive power button problem?

I've had the radio for almost two years now, with no prior issues.