Roku - video in a small box

[roba]

Using HDHomeRun FLEX 4K (firmware version 20250815) on a Roku 3800X streaming stick sw version 14.6 with the HD HomeRun app version 104.0 build 20250817. Tuning many ATSC 1.0 stations the video appears in a box in the upper left corner of the screen with the rest of the screen a solid green background. Sound works fine. I've tried adjusting the Roku display resolution from "auto" to 720p and 1080p but that doesn't change the display. How can I get the picture to take up the whole screen?

The HDHomeRun FLEX worked fine on the same TV with a Chromecast with Google TV, but I had a lot of buffering issues with that device. The Roku isn't buffering, but has the scaling issue.

[nickk]

Do you see this on all channels or specific channels only?

[roba]

There is one channel that displays full screen, most other channels are about 75% and one is 25% of the screen. I sent diagnostic data tuning some of the channels about 10 min ago 10A4BCDB in case it is useful.

[roba]

Example image:

[signcarver]

It wouldn't surprise me if it were roku but that almost looks like a tv setting i used to have as to whether or not the tv filled the screen with the video or played it exact size and or a fixed setting of the tv resolution (sometimes by port)

I've also seen such when attached to a 4k avr and the avr keeping such at 4k.

When you switch rohu output from 1080 to 720 does it get slightly smaller?

[roba]

Switching to 720p vs 1080p does not effect the size of the picture. Some stations have even smaller pictures and a couple look normal. I moved the Roku to another television and it does the same thing in the HD HomeRun app. Netflix, Hulu, etc all work fine too.

[jasonl]

There are one or two old Roku models that don't scale MPEG2 video properly. There is no fix.

[roba]

Thank you Jason. Can confirm that this is the issue. I borrowed another Roku and it works fine.