Looks like an audio jack. Is there anything on the inside wall outlets that may match it? I tried to Google wall plates but didn't find anything. Is there a manufacturers name or model # on the plate that is visible to do a search with.
2014 Palomino Puma 25RS
2011 F-150 Super Crew XLT
Days camped in 2014 - 23
Camped 2015 - 47
Camped 2016 - 51 done - 6 more planned so far