I'm having a similiar issue after updating my Roku Ultra to 9.2.0 build 4131-46. Never had the issue before. If I turn off the system (I have Control4 and it's set to go back to the home page when I power the room off) while watching YouTube TV when I power it back on and go directly into YouTube TV my stations only show in the top left 1/4 of the screen. If I go back to the home page, then go back into YouTube TV it seems to work fine. Haven't noticed any issues with the other apps but I use YouTube TV 99% of the time.
I just bought the Roku 3930rw and started streaming using the Spectrum app. It worked fine until I went to Pluto TV and set up an account there also. It worked fine on a couple of channels (I don't remember which ones, one was a movie) and when I went back to Spectrum at first all the local news channels were scrambled pictures. I went back to my antenna channels to watch the news and then back to Roku to watch the TRVL channel. Everything there was fine until the actual show started and it was now 1/4 screen. ONLY the actual airing shows shrink. Every other screen is normal. I tried several other channels and all of them did the same thing but now the local news channels are visible just shrunken like the others. I saw this post and tried full disconnect and reconnect. It looks fine now but I'd bet it will come back the next time I change streaming apps. Brian F.
My Roku Express+ 3931RW has stopped having the 1/4 screen issue. I don't know why, I haven't changed any settings since my first set up on 11/06. My TV is an LG-32LD350. On the first day I had the Roku, I resolved the issue by going to Settings > System Restart. I did this several times. Since that day, the Express+ has not had the problem.
Can't figure out how to post a picture. Roku Ultra is connected to a Onkyo receiver which is connected to a Sony 4k TV. Never had any issues before the latest update.
@Katmac13 Thanks for letting us know about the issue you ran into. Would you mind providing the specific make/model of TV that your device was connected to?