Best resolution? Hz always changing

Hi,

Not sure whats wrong with my setup but i have a 4k monitor and running it on 3840x2160 at 60hz , I can play Train simulator 2021 and it stays at that resolution at 60hz,

But soon as i click Load on a Openbve route/Train and it goes into full screen it stays at resolution but it some reason keeps going down to only 28hz and i have to manually go into the windows screen and change it back to 60hz and then click the maximize button and it stays at 60hz ? 

Not sure if there is a fix/issue

Kind regards

Raymond.

I don't have a large enough resolution available to test that (only goes up to 2560x1440...)
60hz seems to work OK for that.

Dropping to 28hz though possibly suggests you've got Vertical Synchronisation (VSync) enabled.
This attempts to keep the framerate at an exact multiple of your resolution.

The other thing to try would be to use windowed mode at 3840x2160, but in the current release version, the taskbar would be shown on top.
I've tweaked the daily builds to sort that today.