Servo Actuating Prematurely

[Luke3161]

Hi,
I am from team 3161, and we are having problems with a servo on our minibot deployment system.
A servo is used to release a drop down rail which the minibot is then launched from. This has appeared to work fine while we are on the practice field or in the pits. But, when we get onto the field, it actuates every single time around 30 seconds into the teleoperated period.
We can control the servo, run and stop it throughout its full range of motion. We have also left the robot running for at least 3 minutes in the pits while tethered, but we cannot seem to be able to reproduce the problem.

Any advice would be greatly appreciated.

Thanks.