My Q10 pro arrived yesterday. I also have issues and I am using a Synology server with DS Video.
Many 1080p 24 files are displaying the incorrect framerate, sometimes 24p films play at 50hz or 60hz and don't upscale to 4k. Certain 4K files I just get a black screen with audio too. I am a little confused by the settings. I have the box set at 2160p 60hz in the settings. If I enable that checkbox for the auto frame rate switching in the actual android settings then it really plays havoc with resolutions and framerates, with that box ticked they are all over the place, even not upscaling 1080p to 4K on an LG OLED HDMI 2.0a TV.