Dont know exactly for your box but I'll thing they run same basics.
Do you have kind of two different menu that handle settings? I do, one is very similar to regular android settings and the other feel somewhat more box/tv settings, anyhow in this second settings menu there is a variety of hdmi...
Look for the setting Adaptive Frame Rate (or Auto Framerate Refresh) android also have a setring for hdmi (self-)adaptation that will enable switch 50/60hz.
Much dependant on your display and it's features aswell.
Hope I clarified something at least :)
Also like it quite alot and will probably keep it as main player. Some issues and notes following:
Refetch of full list/epg if you switch user.
Automatic start of first channel in each group makes the navigation slow and choppy.
Lack of AFR switching.
Navigating in EPG-view is awkward and I tend...