FrSky TFR4 problem. Really puzzled.

[V6Jim]

Transmitter is a Futaba 3PM 2.4Ghz - SS
Receiver is FrSky TFR4.

Binds fine. Solid green light. Throttle works fine. Turn the steering a few times and boom, loss of signal. Red light on FrSky flashes. Does it every time.

I have tried the receiver in another car with a different ESC and servo and the same thing happens.

I have two receivers and both do the same thing.

Both cars work fine with other radio equipment.

Totally bamboozled!

Help,

Jimmy