I am using a Sonos Beam as my only speaker for my TV. I am wondering if it i possible to output 5.1 sound through that? I just want to confirm that it doesn't because it is a single soundbar setup and not that I screwed up the setting.
You're not going to get 5.1 sound out of a single speaker. The numbers refer to five full-bandwidth speaker channels (typically front-left, front-right, rear-left, rear-right, and center) plus one low-frequency channel (a sub-woofer).
Without any additional speakers, you'll only get 3.0 from the Beam (left, right, center).