[Vex] Spontaneous channel switching/dying

We are having an unusual problem with our vex elevation robot. Controls from Rx1 work fine. However, for about one boot out of every four, about 30 seconds after teleoperated mode begins, signals from Rx2 begin to undergo a bizarre, repeated, pattern:

Channel 5 (controlling motors 5 and 6) does not work
Channel 4 (controlling motor 7) instead controls motor 8
Channel 3 (controlling motor 8) does not work.

After about 45 seconds of this, the robot returns to normal.

Rx2 Light remains on at all times, and no code error light flashes

This problem has never occured under tether, but its occurence is inconsistent enough that i could believe that this is a coincidence

Any suggestions as to why this might be/how to solve it?

Are you stalling motors? The VEX controller will start to do weird things if the battery voltage drops below 5volts. This usually occurs in the controller restarting, often in auto mode in the middle of a match.

Our robot had similar issues but we found that to fix it all you normally needed to do is turn your control off and on and everything worked fine.
Nick