Martin Yeates

Can anyone help please? I recently upgraded from my old Futaba challenger set that was very easy and succesful including the "buddy" system. After much consideration I bought the Hitec Aurora9 and an Optic 5 transmitter and buddy lead. When I first arrive at our flying site, set up the two transmitters for training and have a succesful 1st flight, great no problem. However, after refuelling etc, power up the transmitter and the trainer system will not work! The display on the aurora shows that the switch is putting the transmitter in to training mode, but it does not ACTUALLY transfer control to the other transmitter. This sequence of events has happened for several weeks running. Allways works 1st time, then is unreliable for further flights. If it does work on a further flight, it is fine, i.e never stops working during a flight. Any idea's?