I have had a FrSky X7 Taranis Q transmitter and X8R receiver for several years without any problems. The Rx is mounted on the electronics tray of my Northlight puffer. A few weeks ago there was a minor problem with the boom pulley system. Putting it right did not go smoothly (the ravages of time have taken their toll on bone and brain!). I ended up having to re-thread the whole system! This required removing the electronics tray (which has 11 connecting leads).
On re-connecting, all channels were working but, a few days later, when demonstrating the system to great grandson, I found only Ch. 1 (throttle) was working. I plugged Ch. 2 (rudder) into Ch. 1 and it did not work and neither did the throttle plugged into Ch. 2. (The Rx LED = green)
At this stage, I found an 800 mA fuse had blown - this in line from auxiliary 6v battery supplying bilge pump (non RC), winch motor, hoist and raising/lowering the boom. Having replaced the fuse, no channels on the Rx work and it's LED is red. (I couldn't find a reason for the fuse to blow and it has remained intact.)
First thought was to try rebinding the Rx to the Tx. After numerous failed attempts, have given up. Before investing in a replacement Rx, I wondered if anyone could shed any light or offer an opinion!
Mike