I don’t think it’s the GPU as it’s the same one as in the MXQ’s and anyway the main CPU does most of the image processing. I’m beginning to suspect that it’s the thermal solution on these older boxes. I might try re-gluing the CPU heatsink and maybe running it from start out without the bottom of the unit on.
Again I suspect that many older boxes, but also newer ones, have issues with temps. Older boxes were often designed to run at 720p but had the firmware updated because of the Kodi and HD craze. Older boxes are pushed to their limits and will probably overheat playing HD video and certainly playing 4K. Playing 4K is one thing put playing it consistently without glitches is another.
I don’t do 4K so I’m miffed that these older boxes struggle with 1080p or even 720p. As I keep saying my old MXQ’s (S805) running Jarvis are pretty good and even better with a heat sink added. So I’ll experiment, if I get time, and see if adding cooling helps minimise or even eliminate the stutters.
It may be that older boxes should be put on a different list with a note saying that playback may suffer due to the specifications of such boxes.
EDIT: For now I’m just going to run the NEXBOX A95 upside down due to it’s design as this will help heat dissipation through it’s vent which are on the bottom. If that doesn’t work then I’ll get more drastic. As for the Beelink Mini MX I’ll have to open that up and have a look at the cooling solution as it doesn’t have any vents.