Had the same problem with a T72 it was my fire button. Had to take the TX apart and clean the button pad with electronic parts cleaner.
To find out open the TX and switch the CONTROL BUTTON CABLES around. I have lots of 1/24 vs and FOV tanks tried 1/16 HL ran well no problems. Just like 1/24.
Also they have a lot of 1/24 and 1/20 figures out now. The tanks run well outside on dry dirt.

I also have a call into IMMORTAL HOBBIES for a VS TK 22 that is compatible with a Tamyia system. They told me they could get one but never got back in touch. Probably don't car about us 1/24 guys.
Also I open up the trans. and make sure there are no barbs on the gears and then fill them up 50% with spray lithium grease. I grease all the gears in the tanks (works a lot better )
Also on FOV get rid of the battery box and connector and use a 7.2V 3/4A cell 1600 ma r/c battery pack. It slows down the tank runs more realistic. The VS tanks have 2 power take offs
so you have to rewire it for a 8.4 3/4 A cell pack plus cut out the battery compartment with a Dremel tool (need to compleat this ). But wanted to do the TK22 thing first on a zero vs tank.

To me 1/24 tanks are like Lionel Trains trains thay are starting to have it all and fit anywere.
I see the 3 major groups will be 1/72,(1/24,25) and 1/16, just like trains.

Well I just had ti rant some were sorry. Hope this helps and I have the time to do the things I want to with 1/24.
Also I'll take all the input I can get on making 1/24 tanks reach a thousand dollars each (no toys here).