Schumacher CODE 2.4Ghz transmitter (probs)

[Cooper]

Hi everybody :-)

I've recently purchased a CODE to replace my oldskool KO transmitter,
since the beginning I've had some troubles with the car switching off, a "off"-"on" with the ESC switch made the car work again.
This happened 1 time on a training day, another day 2 times and last sunday I had to stop my national because every qualif round the car stopped after the "Kampenhout wall" and after it was switched on again, a couple of turns later in went of full speed, crashed into something and stopped working again.
Another thing I had 1 time is a SLOW servo, after a "off"-"on" it worked again normally.
I've changed to gold contacts and resoldered the wires where they are on the ESC, none of this helped.
The transmitter is now back to the shop and they'll send it back.
If anyone has some ideas what could be wrong, please share :-).

my setup:
CODE Tx and Rx
trakpower 4900 lipo
Tekin RS speedo
speedpassion 3.0 7.5t motor
black tires