My setup is with NAS my book live and Denon x1400I experience the opposite. Smoother interface of kodi better playback and better functionality of screen settings and auto display switching.
With a stream add on movies playing smooth. All movies play smooth that are on my NAS.
What is your setup? with or without a NAS. How is your NAS configured.
Second is that the CE still a beta version of Kodi leia
You can try stable version of Kodi 17.6
There are also streaming plugins that can make things smoother I read someday.
Or try LibreELEC if you experience the same.
Try settings on display, on network samba, or nfs
3th this is still custom rom on your minix but it should work.
It reads all formats in android 17.6 on Minix as it is on CE and managed to get streaming in CE but clared all white list resolution
Dont know is picture quality a bit better on CE 8955
Most off problems is with pvr iptv simple and constant freezing