How can I speed up the AN-225?

See:

The issue is Throttle 1 is controlling Engines 1-3, but Throttle 2 and Throttle 3 are also controlling Engines 2 & 3, respectively, and they fight each other.

I found, with my peripheral’s 4 throttles, I have to just use throttle 1 and throttle 4 and not touch throttles 2&3. The other solution is to just unmap throttle 2&3 just for use with the 225.