I have both a 4k Roku stick and 4k Firestick. I prefer the Firestick, but since Apple Airplay is now possible on the Roku, I want to plug them both in. I have a spare hdmi port, but no spare USB port in the back of my TV. In any case, the Roku draws too much power for the usb. The cable I have for the Firestick has some kind of inline booster (I bought it after having the same issues with the Firestick), however it is micro usb whereas the Roku is mini usb. Anyway, I thought it would be possible to power them both of some kind of dual usb power bank, with the TV usb trickle charging the power bank at the same time. Anyone know if this would work, and if so, can they recommend a power bank for the job? It would obviously have to output enough power to the sticks, although I would only be using one at a time. It would also have to have enough battery capacity to last for a good few hours whilst being charged at the same time and be small enough to tuck behind the TV (my TV is wall mounted, so would probably tie it to the wall bracket).