Ham if your only have intermittent issues at the track then your getting a cross signal from interference or its a Heat issues. It could cause a thermal shut down. I owned a futaba for years never had this issue thou

I would buy a extra receiver anyway as backup. Then swap out to see if the issue goes away. Also try to rebind the units maybe that will help. Also you can do factory reset but you will loose your settings.

Anyone running flyski radios, I heard these cause havoc on other transmitters but I believe it was spectrum