Significant stuttering and artifacts with 1080p H.264 file

So I tend to use the Social Network blu-ray (ripped to MKV with makeMKV) to torture test players, mainly using the slow panning shot that starts at 5:32. On the latest build (1.19, 7339), there is significant stuttering during this scene. Even before this scene though, though, there are weird artifacts that look like macro-blocking with fast movement (like when Zuckerburg gets up out of his chair in the cafe). Per PMS, the video is being direct played, but the audio is being transcoded to AC3. This problem is not unique to the beta though; it’s also in the non-beta build (maybe I should post over in that forum?). The same file plays back perfectly fine in Infuse. This is on the tvOS 11.2 beta (although I had the same issue on 11.1).

Media
Video Resolution 1080p
Duration 2:00:27
Bitrate 30472 kbps
Width 1920
Height 1080
Aspect Ratio 1.78
Container MKV
Video Frame Rate 24p
Audio Profile ma
Video Profile high
Part
Duration 2:00:27
File The Social Network (2010).mkv
Size 25.64 GB
Audio Profile ma
Container MKV
Indexes sd
Video Profile high
Codec H264
Bitrate 27400 kbps
Language English
Bit Depth 8
Chroma Subsampling 4:2:0
Frame Rate 23.976 fps
Height 1080
Level 4.1
Profile high
Ref Frames 2
Scan Type progressive
Width 1920
Codec DCA
Channels 5.1
Bitrate 1536 kbps
Language English
Audio Channel Layout 5.1(side)
Bit Depth 24
Profile ma
Sampling Rate 48000 Hz
Title Lossless
Codec DCA
Channels 5.1
Bitrate 1536 kbps
Language English
Audio Channel Layout 5.1(side)
Profile dts
Sampling Rate 48000 Hz
Title 3/2+1
Codec PGS
Language English
Codec PGS
Language English