have you used the same AVR with other speakers? Or is this your first time using it?
On a side note my Marantz shows reverse phase when I use XLR to my amp but doesn't show it when I use RCA to my amplifier. I thought the XLR were wired wrong but I checked and they were correct then after a google search I saw others had the same issue with using XLR on Marantz AVRs. Something about some Marantz models use a European XLR standard which is reverse of American or old standard vs new. The link below covers it somewhat.
HTPC, Sony 40es, Marantz 7702mkii, Sunfire Cinema Grand 225w x 5, JBL 590, JBL 520
PSA XS30, Seaton Submersive, 2 Um-18 8cf sealed, Outlaw Ultra x 12, Kappa Pro 18LF, BFM Tuba 60 horn, B&C 18TBW100 6cf 41hz, 34hz, 28hz tune
iNuke 3000 & 6000 DSP's, Crowson Motion Actuator