spiderbox +DiSEqC Switches

hi all, is it possible to use a 2 way DiSEqC Switch for two dishes into the back off my spiderbox. at the moment i am using an a-b switch which is outside to choose which dish i want and it works great. got a two way
Tm DiSEqC Switch and tried to connect it but no luck. the problem is one dish is motorised and the other a fixed dish but it has a monoblock on it to get 39e and 42e. also using a v-box to drive the dish.
will the built-in DiSEqC Switch in the monoblock inter fear with the two way switch or is it the way i have set it up.
thanks.