Thanks for the responses, ptaaty & pmbuko.

I switched the speakers and per ptaaty’s expectations, it did not make a difference.

I also switched the phase on the sub to 180 to rule out the sub being out of phase in general. The switch to 180 reduced the “db’s delivered” and did not help the right side.

So then I walked around with the spl meter to check out the “destructive” interference with the sub and right speaker, the only place where there was only little destructive interference was right in front of the speaker (within 2-3 feet).

Unfortunately I do not have options to move around my sub or speakers, so I will live with the “destruction”.

Does anyone have any idea how much I am “missing” in the way of fidelity? Since I am only having the problem with one speaker, are there any adjustments I should make to compensate? Like increase the db’s on the right speaker?