I recently bought a used P3 4K. It worked fine until one day the remote wouldn't turn on or charge, and the wifi was turned on. Searched the forums for this problem, and found that disconnecting the battery for a few seconds will fix the problem. And it did, until the next time, and the next time. Got to be an expert taking the thing apart to just unplug the battery for a second. Finally enough is enough, I installed a DPST switch to disconnect and reconnect the battery when required, now all is well in the world again! A quick flick of the switch off then on again and I'm back in business. I mounted the switch on the back near the usb port. It's out of the way and not much chance of accidentally hitting it.