External monitor playback crops for no reason.

[Rene5EC5]

Hello.

I have a dual monitor setup and if I do something in my timeline my external monitor footage crops in for no reason and It won't go back unless I disconnect my external monitor from "playback" settings. It doesn't freeze or anything but it just crops in and it is impossible to work like this.

I have tried different monitors and done updates but it still is happening. I think it might be like 150% crop. Sometimes it won't crop in but sometimes it does very fast. 

[Andy 1968]

Is it a computer monitor or a TV. TV's have a zoom on the remote control.

[Rene5EC5]

External monitor is a TV BUT I have tried computer monitors and other displays.