Video Format

HDR Plus is an enhancement of HDR 10 that’s about adding on the fly settings adjustment and other features that have nothing to do with the brightness scale

Most displays that do HDR are closer to 400nit. That’s a hardware, not a format limitation

It depends which HDR+ you are referring to:

- HDR+ (found on older models): My understanding is this is basically a fake HDR....the TV interprets and SDR signal and then extrapolates it to an HDR image. Basically, found on cheaper models;

- HDR10+ (found on newer models): This is, in essence, HDR but with some extra bits thrown in. The image is still the same quality, it just has extra. This article explains the differences between normal HDR10 and HDR10+:

https://www.samsung.com/africa_en/tvs/tv-buying-guide/what-is-hdr-tv/

It's possible the website changed the video format, hence why you get unsupported browser. There is nothing you can do but wait to see if the change the video format again.

Hey TwinTax0699. What would be the format of the videos you CAN see? Also, what would be the format of the videos you CANNOT see? Where did you get these movies?

Just to clear it up really quick .MKV is a media container format and the video and audio inside could be encoded in almost any format. Anything from MPEG2 video to 10Bit h264x for video and MP3 to DTS-HD for the audio. Also the format isn't widely used
by legitimate content sources and Windows 7&8 don't have native support for the format. If you really want you can always remux the files into a different container or completely re-encode the file into a format supported by the 360.