IOS 10 / Slingbox

[PB&J]

Since upgrading my iPhone to iOS 10 have the following problem; I use my iphone and sling box to play live tv for my kids in the car. Before the iOS upgrade, the tv out feature filled the entire screen in the rear seat monitors. Since the upgrade the picture fills about 70% of the screen. I have tried resetting everything - sling box pro hd - my iphone - and inputs (component) to no avail. My wife's phone (not upgraded) still fills the entire screen so I believe the problem is related to the upgrade. Any suggestions?