Funny you mention that, something similar happened to me last time I flew (that's not normal). I was in a different building for the first time. I'm thinking it could be caused by some interference from the building's metal framework/HVAC- I'll look into the effects of being inside a Faraday cage. I'll let you know if I have the same trouble when I go back to my other spot.

Are you inside a building? Has your radio gear functioned properly up to now? Problems there could cause your tail rotor trouble. Are there any loose receiver plugs?