Transcoder crashing on only some H.265 videos

I am running Plex Media Server Version 1.7.4.4017 on macOS Sierra 10.12.5. I have several DVDs that I’ve ripped with handbrake using the H.265 MKV 480p30 preset. Most (but not all!) of them crash instantly when I attempt to play - I’ve tried from the server via the web client, the AppleTV client, and the iOS client. The attached logs are from trying with the web client.

Here are some details on one of the files that crashes (see below for similar detail on a file with same settings that plays fine):

==========

$ mediainfo La\ Storia.mp4
General
Unique ID : 99703433637432269270267835066839851358 (0x4B022ECE9B1B5E621F6AAA61B2F9E15E)
Complete name : La Storia.mp4
Format : Matroska
Format version : Version 4 / Version 2
File size : 152 MiB
Duration : 31 min 28 s
Overall bit rate : 673 kb/s
Encoded date : UTC 2017-06-27T22:06:09Z
Writing application : HandBrake 1.0.7 2017040900
Writing library : Lavf57.7.2
FileExtension_Invalid : mkv mk3d mka mks

Video
ID : 1
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main@L3@Main
Codec ID : V_MPEGH/ISO/HEVC
Duration : 31 min 28 s
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Writing library : x265 2.1:[Mac OS X][clang 8.1.0][64 bit] 8bit
Encoding settings : wpp / ctu=64 / min-cu-size=8 / max-tu-size=32 / tu-intra-depth=1 / tu-inter-depth=1 / me=3 / subme=3 / merange=57 / no-rect / no-amp / max-merge=3 / temporal-mvp / no-early-skip / rskip / rdpenalty=0 / no-tskip / no-tskip-fast / no-strong-intra-smoothing / no-lossless / no-cu-lossless / no-constrained-intra / no-fast-intra / open-gop / no-temporal-layers / interlace=0 / keyint=240 / min-keyint=24 / scenecut=40 / rc-lookahead=25 / lookahead-slices=0 / bframes=4 / bframe-bias=0 / b-adapt=2 / ref=4 / limit-refs=3 / limit-modes / weightp / no-weightb / aq-mode=1 / qg-size=32 / aq-strength=1.00 / cbqpoffs=0 / crqpoffs=0 / rd=4 / psy-rd=2.00 / rdoq-level=2 / psy-rdoq=1.00 / log2-max-poc-lsb=8 / no-rd-refine / signhide / deblock=0:0 / sao / no-sao-non-deblock / b-pyramid / cutree / no-intra-refresh / rc=crf / crf=20.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ipratio=1.40 / pbratio=1.30
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.601 NTSC
Transfer characteristics : BT.709
Matrix coefficients : BT.601

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : A_AAC
Duration : 31 min 28 s
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 spf)
Compression mode : Lossy
Title : Stereo
Language : Italian
Default : Yes
Forced : No

Menu
00:00:00.125 : :Chapter 1
00:04:04.703 : :Chapter 2
00:08:26.381 : :Chapter 3
00:12:18.071 : :Chapter 4
00:17:13.866 : :Chapter 5
00:21:49.975 : :Chapter 6

==========

$ mediainfo Wedding.mkv
General
Unique ID : 261241920886300527521050986317790336569 (0xC4895D23129BAA3419808C91C2305639)
Complete name : Wedding.mkv
Format : Matroska
Format version : Version 4 / Version 2
File size : 258 MiB
Duration : 26 min 59 s
Overall bit rate : 1 336 kb/s
Encoded date : UTC 2017-06-27T19:33:33Z
Writing application : HandBrake 1.0.7 2017040900
Writing library : Lavf57.7.2

Video
ID : 1
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main@L3@Main
Codec ID : V_MPEGH/ISO/HEVC
Duration : 26 min 59 s
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Writing library : x265 2.1:[Mac OS X][clang 8.1.0][64 bit] 8bit
Encoding settings : wpp / ctu=64 / min-cu-size=8 / max-tu-size=32 / tu-intra-depth=1 / tu-inter-depth=1 / me=3 / subme=3 / merange=57 / no-rect / no-amp / max-merge=3 / temporal-mvp / no-early-skip / rskip / rdpenalty=0 / no-tskip / no-tskip-fast / no-strong-intra-smoothing / no-lossless / no-cu-lossless / no-constrained-intra / no-fast-intra / open-gop / no-temporal-layers / interlace=0 / keyint=240 / min-keyint=24 / scenecut=40 / rc-lookahead=25 / lookahead-slices=0 / bframes=4 / bframe-bias=0 / b-adapt=2 / ref=4 / limit-refs=3 / limit-modes / weightp / no-weightb / aq-mode=1 / qg-size=32 / aq-strength=1.00 / cbqpoffs=0 / crqpoffs=0 / rd=4 / psy-rd=2.00 / rdoq-level=2 / psy-rdoq=1.00 / log2-max-poc-lsb=8 / no-rd-refine / signhide / deblock=0:0 / sao / no-sao-non-deblock / b-pyramid / cutree / no-intra-refresh / rc=crf / crf=20.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ipratio=1.40 / pbratio=1.30
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.601 NTSC
Transfer characteristics : BT.709
Matrix coefficients : BT.601

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : A_AAC
Duration : 26 min 59 s
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 spf)
Compression mode : Lossy
Delay relative to video : 33 ms
Title : Stereo
Language : English
Default : Yes
Forced : No

Menu
00:00:00.149 : :Chapter 1
00:06:50.559 : :Chapter 2
00:09:18.916 : :Chapter 3
00:12:57.509 : :Chapter 4
00:15:41.882 : :Chapter 5
00:17:21.815 : :Chapter 6
00:19:34.489 : :Chapter 7
00:22:09.561 : :Chapter 8
00:23:38.608 : :Chapter 9

==========

Thank you! Subtitles seems to be the problem. For now I will disable them and aim to reencode to H.264 at a later date.