I thought the 955 was a single conversion and the 945 was a dual conversion.

Are you using any match boxes? We had one that went bad and we couldn't get more than about 20 feet away before going into failsafe.

Start unplugging leads from your RX one at a time to see if you can isolate any of those items as the cause. Make sure all of your battery leads are run as far as possible away from the fuel pump wiring.