It depends what EXP input the aux switch is connected. If connected to EXP 1, they will correspond to 1,2,3. If connected to EXP2, they will correspond to 4,5,6. As to whether or not the EHX is already wired internally in such a way that the H90 will sense them in order (switch 1=4, switch 2=5, switch 3=6), let’s let the EHX users chime in.
