Need to determine which of the 4 HDMI ports on my Series 550 (Plasma) is to be used for ARC (Audio Return Channel) to hook up a Sonos Beam soundbar. I've tried various combinations, but haven't had any success getting this Beam set up. Currently using Optical connection, but not very happy with that since it's Stereo and want the ARC/HDMI hooked up for Dolby Digital. Any other considerations?
... View more