HABOA HYPER 7 NEED HELP NOOB :)

[apple_fanta]

i recently purchased a brand new hyper 7 .28 nitro buggie car 1/8th scale and since have had a few problems nothing major however.
the latest problem seems to be the throttle servo.
lately ive been running the engine in on 16 percent nitro fuel and of course lately its been snowing. ive been running it in the snow but had the shell on. the problem is this. the servo that the throttle is worked on keeps opening and closing on its own when it is turned on with both the transmitter and receiver, however when the transmitter (the remote) is off it doesnt open and close on its own. ive tried using my mates transmitter with a change in crystals however have the same problem occuring. has moisture gotten into this servo causing the throttle to open and close itself? it also seems to jam sometimes almost like it has difficulty retracting to normal position. any help is appreciated