As an FYI, Live TV suffers from this same issue on the 918+ for both .1966 & .1973. The entire view shows artifacts. I had mentioned it here. I suspect it has to do with the updated drivers used for transcoding.
I did not have these artifacts in .1944.
Wow, a little salty this morning @trumpy81!
I was just adding that in versions 1.18.1.1973 & 1.18.1.1966 show similar artifacts with Live TV and subtitles. Yes, I did ābotherā to check the screenshot which is why I brought it up - please see the attached screenshot:
Now, subtitles off:
In 1.18.0.1944 Live TV would buffer every 30 seconds or so with subtitles on, but at least youād see a picture whereas 1.18.1.1966/1973 show the artifact view until you disable subtitles on Live TV. Since the 1.18.1 line of Plex uses a new driver (at least for the intel iGPU from what Iāve read), I suspect it has to do with that.
I have broken this out of the original thread.
This is sufficiently different that it should have its own thread.
EIA subs are OTA TV related and not the topic of that thread.
I am investigating some reports of EIA subtitle issues.
Your supplied image show complete image breakdown which I attribute to the main codec breaking down .
We need to recreate a controlled test case with and without subtitles
Thanks @ChuckPa. The image looked similar, which is why I posted about it in the other thread.
Would you like me to upload logs?
I reverted all the way back to 1.18.0.1913 and confirmed the image breakdown did not occur in 1913 or 1944 (although those versions exhibited the buffering around every 30s with subtitles enabled in Live TV).
Versions 1.18.1.1966 & .1973 show the first image until subtitles are disabled for OTA. I have not tested any image based subtitles (ie: PGS) for existing media content.
I recommend you remain at 1.18.0 if you can while this is investigated.
A number of changes were made, some at the last moment due to a whole host of external reasons coalescing & (feels like) āconspiringā at the same time.
Thank you for the feedback. Iāll probably revert back to the 1.18.0 line until another 1.18.1 release is made.
No problem. I understood that we were talking existing encoded video vs OTA stream -> plex -> stream -> client, but I didnāt know if the EIA_608 subtitle type from OTA was an image type similar to the OP in the other thread. After my own investigation it seems EIA_608 is actually a text type subtitle stream (although it seems like it needs to be transcoded like an image subtitle type) and yes, I should have made a separate thread about it but the output was similar so I thought it might be of interest. I had linked to the other thread where @iced98lx mentioned 1.18.1.1966 was a lot better, unless he enabled subtitles from an OTA source and he and I had the same problem as I screenshotted above.
Wow, that is interesting to know!! I was able to disable hardware transcoding on previous Plex versions and if I recall correctly, it behaved a little better with OTA - even on the DS918+ (not 4k content, obv). Iāll give that a shot in 1973 for OTA and see where I land (obviously, that wonāt be the go-forward solution, rather a data point) and post what is displayed.
Well, I donāt know if this is helpful at all, but I disabled hardware transcoding for the server and sure enough, subtitles for Live TV worked fine AND I didnāt get the massive artifcating on initial stream setup. Clearly my CPU is being hammered, but hopefully this will help.
FYI, CPU utilization with hardware transcoding was in the 20-30 10-15% range for Plex.
Honestly, I canāt tell you what I did to get them to workā¦ Iāve seen threads here in the Synology forum saying they didnāt report, and even more reports on current versions saying they didnāt work and I didnāt know why. I believe ever since Iāve setup the DS918+ both CPU and RAM have reported on the Plex dashboard.
Iāve only had the Synology for about 2 weeks. I first upgraded DSM out of the box, then installed Plex from DSM (like 1.16 or 1.17ish?), then fought with permissions, then upgraded the .spks directly from Plex.tv through DSM.
Iām trying to move my Plex install from a desktop to the Synology and havenāt quite decided whether itās worth the hassle 
. I have another job tagged for the PC, so Iād really like to make it happen.
Oh yeah, I know! It was really just a test to see if it would work at allā¦ which even on a DS918+ with a J3455 itās clearly not able to keep up!
Graphs have always worked on my 718+ ironically, and I donāt want think about it too hard or theyāll stop 
I am having the same exact issue with Plex on 918+. If there is anything I can do to help, shoot
There is a workaround while being fixed.
This certainly helps, after the buffer seems to catch up (about 20s in the beginning). Is the driver being fixed, or is this driver fallback going to just happen automatically?
Two development efforts are at work:
Intelās roadmap is to support only the iHD driver.
Any news regarding this issue? An update came out but Iām still unable to watch anything on my RokuTV
There is a workaround and progress I can report:
The problem with the iHD_video_drv.so (Intel provided) has been reproduced and being worked on . Results are promising but not yet ārelease readyā.
The workaround, which is good for the current version of PMS you have installed is to delete the iHD_video_drv.so module after installing PMS. PMS will fallback to the i965 driver (which is ok for all but the most extreme video bitrates and conversions). Everything will be (temporarily) back to normal.
How-To:
[chuck@lizum ~.178]$ ssh -l admin 192.168.0.23
admin@192.168.0.23's password:
admin@moesern:~$ sudo -su root
sh-4.3# cd "/var/packages/Plex Media Server/target/lib/dri"
sh-4.3# ls
i965_drv_video.so iHD_drv_video.so
sh-4.3# rm -f iHD_drv_video.so
sh-4.3#
Is an update to PMS being developed to fix this video artifacting problem when subtitles are turned on? Some of us are hearing impaired and rely upon subtitling to help.
