Refresh rate switching Pi3 vs Minix U-9H

Raspberry Pi has a tightly integrated kernel and decoding stack that are attentively maintained by the Pi foundation developers because over time good Kodi support has helped them sell lots of boards which means more $$ for their charity work. On the other side you have a festering turd of an Amlogic board-support kernel supporting the manufacturers limited range of Android test cases that has been repeatedly "fixed" over a long time period by inexperienced community developers who lack the experience to architect and author good code. On the Kodi side this is partnered with a vendor-proprietary code interface (amcodec) that was originally created by the same team who made a mucking fess of the kernel code and has since been repeatedly "fixed" by the same community developers who lacked the low-levels skills to fix things correctly in the kernel. It has seen some cleanup in the last couple of years but hacking Kodi to workaround deficiencies in the kernel is the long-term unsustainable trend.

TL/DR; RPi runs great code but lacks the grunt for 10-bit content. S912 devices have the grunt but are forced to run lower quality code. Both run Kodi the app, but internally they use different and not equal code paths.