model number: 55UB7500
these are what the overscan settings look like: http://imgur.com/a/qrHmtZb
i have the same issue with same tv. have u found the solution? its overscan. we fix it by adjusting overscan. but we cant save the changes.
Did you try checking the tv's developer options menu?
This isn't likely to be an Android TV issue - that menu isn't part of the OS, and is the TV's firmware.
If that's a Google Chromecast with Google TV, you can shrink the image in the settings, so you won't lose the edges.
Most TVs also allow you to change your HDMI setting to either "PC" or "Game" which removes any overscan and processing. That would be rather better - it looks like a heavily over processed picture to me.