Line out Einstein 100w head

I use the line out to feed a Gmajor processor and then to a 20/20 boogie. I find that no matter what I do with the line out pot. that it isn't reflected in the major input signal. With the pot off signal is still getting to the processor.Any suggestions or explanations?

This is something I don't get, I don't own a Diezel but...why would you use the G Major then into a power amp? Why not use the effects loop?

Because the processor is my wet sound and the head into a cab is my dry sound.