OpenTK project performance issues?

I am developing 2D game using monogame and I am facing some stuttering issues.
I have 3 different versions of game sharing the same code prepared - Android, DesktopGL and Windows (SharpDX). It seems like there is something wrong with OpenTK. SharpDX version works nearly flawless, but on DesktopGL I am experiencing framedrops. In general game runs at 60 fps, but sometimes it can drop up to 10 frames within second. On Android things are even worse. The most probably this is not a Mono GC issue, there is only 0gen collection happening sometimes.

I also prepared very simple project just with scrolling rectangle and there are also framedrops (less, but still noticeable).

Am I missing something? Or is this really OpenTK issue?

Best regards,