How did you initially setup your phase?OK I have done some more tests..
without the DSP1124, the null happens at phase 0
with the DSP1124, the null is at phase 180 (bypass mode), so it is indeed flipped around 180.
It would seem I should leave it at phase 0 then. However after equalizing I get no null only if I leave the knob at 180, so there it is. Once I leave 180 the null gets bigger and deeper.
So that is the final setting.
A bit confused by your above comment that you did more tests and you found the phase was switched only on bypass mode or it was switch on bypass and eq mode?