[SootAndPooh]

I use 10 bit BT.2020 on the shield with resolution set to 4K. I tend to flip back and forth. (1080p for cable and "normal" content and 4K for UHD files) I noticed if I change just the resolution the Shield auto picks the appropriate color space saving a bit of time. The reason I switch is so I can use the TV's upscaler and also for my AVR's on screen volume indicator which won't overlay on top of 4K. The one catch with SPMC is the MediaCodec (Surface) hardware acceleration option HAS to be on for HDR to work. (You need to have it off to use SPMC's high quality scalers like Lanczos3)

Also I don't do any refresh rate switching. I leave it at 60 and let the tv do the "5 frames" thing. (120 divided by 24 = 5 frames each) I set dejudder to 2 or 3 and deblur to 0.

Cheers for those suggestions cscoppa. Leaving refresh rate switching off is the only way I can get the 24p files to play without colour banding. While those dejudder settings help I still notice the judder which I don't get if I play the content directly though the TV USB (but then no HD audio passthrough to my soundbar) or if I set SPMC to output it at 24Hz (but then I get colour banding). Starting to think no perfect solution at this stage.