Try do do it as far from the RX as you wire allows it.

I had the same problem the first time I used. I installed neatly ON TOP of the radio box on my NTTC3.

When I was on the drivers stand the car took off alone and stopped on a mattress (yes they have them at the track LOL, imagine the driving going on there). The problem was that in the meantime it grinded the tires before I could stop it.

Put it VERY VERY far from the RX