I’ve noticed a phase (correlations) alert using different venues in MIR 3D.
Real recording, two clean electric guitar panned with MIR L/R and slightly Front/Rear.
With Synchron Wide (HOA DnMx and 115°cardio) the correlation meter is “green” most of the time between +0.75 and +1.
With Pernegg (same mic setup) is the opposite: “orange” most of the time between -0.75 and -1.
I tried to randomly flip the polarity of the mics but the changes are minor.
With the ears I can feel this “flip” when I change venues but both sounds good, different but good.
Maybe I can notice a listening that is a little more fatiguing with the "wrong" polarity.
I’ve read that this polarity warning may indicate a problem, but not always.
With MIR plugin bypassed (but active) same story, with plugin off (dry guitars) the correlation is fixed +1.
Pro Tools with MIR in insert.
Update: switching the main Pernegg mic from "Front of the nave" to "Middle of the nave" the polarity goes to correct values.