Subtitles / FireStick / Cast using iphone / Synology NAS

[Ahole 3]

My heading is spinning trying to soak in everything and learn.  I have mostly used my DS718+ as a file server but have tried several other uses.  In the last 6 months I have been using Emby and I added an HDHomerun 4k OTA tuner as well.  BTW I upgraded the DS718+ to 16gb of RAM.
My latest addition was a Reolink security camera and Surveillance Station.

Maybe I can get several questions in one place:

1) the main question is last night i tried watching Godfather Part II while connecting on my local network with a Firestick.  I re did the experiment tonight to confirm the issues.  I have attached logs.  At 8:09PM I started watching. The video played fine and the subtitles seemed to work fine until 8:15pm.  At that point the video paused, like typical buffering, but when it started back up the subtitles no longer showed up!  Nothing short of restarting everything would bring the subtitles back.  Is the Firestick not capable of doing the subtitles?  Is the NAS not powerful enough to do the transcoding?  In my Emby server settings I have enable hardware transcoding enabled and I have allow subtitle extraction on the fly enabled.

After I failed while trying to watch with the Firesstick Emby app I was easily able to use the iphone app and cast the movie to the Samsung TV with no glitches and subtitles easily working -- is the iphone doing the transcoding and does it work better because the iphone is more powerful than the Firestick??   I typically don't like to cast form the phome and "tie it up" -- I would much rather use the Firestick app!

Any help would be appreciated

2) what is the best way to get subtitles for recorded TV shows that are recorded via the HDHomerun 4K OTA tuner ?

3) I am soon going to setup surveillance video in a new business for my daughter so I am probably going to use the DS718+ for that and purchase a new NAS for my home/office - was thinking about a DS920+  -- would that be a good choice for running a file server, Emby server and Surveillance Station?

 

THANKS

ffmpeg-transcode-d1ada20d-1dba-4435-9258-aad60bdbedb1_1.txt embyserver.txt ffmpeg-directstream-41dc0295-0b70-4c28-92bb-eb9b245e5c1f_1.txt

Edited October 19, 2022 by Ahole

[Ahole 3]

UPDATE :  re #1 above.  I found out that the subtitle issues are device dependent.

IOS / iphone - subtitles work 

Shield TV : subtitles work

Casting to TV on network (DLNA): subtitles work

Chrome (web): no subtitles

PC app (Microsoft Store): no subtitles