A light flashes on the TV when it receives a command (either IR or RF). The problem is that the light doesn't always flash when the power on command is sent from the Harmony, meaning no power on command is received by the TV, presumably because the Harmony is not sending the RF power on command.

The OEM remote sends a IR power toggle command which always works. All the rest of the commands on the OEM remote are IR. Next time I buy any device I will go into the store and check to see if the OEM remote sends IR or RF signals. In my opinion the Harmony works better with IR commands (e.g. you can't teach it RF commands).

I have a firetv box from 2014 that receives RF commands from the Harmony with no problem.

By the way, the tech support person at Harmony (Logitech) told me that the firetv box receives blluetooth commands. Aren't bluetooth commands RF?