Top and bottom letterbox in live tv

Anyone else have issues with the aspect ratio for live TV? I’m using a hdhomerun extend for ota TV in the US. On my firetv boxes abc fills the 16:9 aspect ratio, but CBS, NBC, and fox all have letterbox on the top and bottom. I’m assuming it has to do with the broadcast transmission but I can’t seem to find anyway to force the aspect ratio either within hdhomerun or plex. I’ve messed with different transcoding options all to no avail. Anyone else seeing this? I must be missing something simple.

For anyone else having this issue I was able to resolve it by removing all transcode in the hdhomerun setup as well as in dvr setup within plex.

Did you ever get a solution to your issue? I’ve got the same issue with HDHomeRun connect and android tv client.