And one more important thing, which is visible only in the channel settings. If some potentiometer doesn't give a stable output, the crash is expected with certainty. The remote's FC hasn't appropriate filters, tied to the copters ability to meet the commands. The copter itself will try to do these commands, doesn't matter, they're in contrast with mass and inertia characteristics of the body. Soon or a bit later it will go unstable and almost out of control