Steam Link On Telus TV Digital Box not working

[Elle]

so i got steam link on the telus tv digital box i just got. try it out, and try to play destiny 2. it works fine until im in game, in which a black box covers 75% of the top of the screen. can only see my characters feet on the character select menu. it seems to be the tv box forcing this black box, because its fine on my pc, (which is 5 feet away, both connected via ethernet, just dont have a long enough HDMI cable) but when i click the home button on the tv box remote, the black box covering the game disappears for a sec before going home, clearly showing me the screen is working fine. idk what to do about this, any help would be appreciated

[Elle]

can confirm now, it happens with every game. its PERFECTLY fine until i get into a game