Access from LAN is fine, but remote access is slow

[JoeonyJoe]

Hello everyone!

I have trouble watching my 1080p movies throught a remote connection to my Jellyfin server. I can see my library, but when I open a movie it is buffering slowly, and when it finally loads after around 30 seconds, it can be watched for roughly 10 seconds before another long buffering happens. Accessing from home inside my LAN network yields almost instant loading of media.

My setup:

• Jellyfin running in a container
  
• Nginx for reverse proxy, SSL, and DDNS, also in a container next to Jellyfin
  
• Have my DNS from duckdns, setup to point to my public IP
  
• Ports forwarded (80:80, 443:443)
  
• 500mbit/s download, 40mbit/s upload speed
  
• Moved from my ISP's CGNAT to have a public IP of my own.
  

What I tried so far:

• Checking for transcoding problems. Result: Transcoding is turned off, movies are streamed in Direct Play. Audio sometimes needs transcoding depending on media, but that should not be a problem.
  
• Check nginx reverse proxy settings. Result: I have fully adapted the nginx config provided by the Jellyfin docs. No visible change in behavior.
  
• Playing media in worse quality. Result: Minor differences in loading speeds, still have to wait around 20 to 30 seconds for buffers
  

My specs:

• CPU: Ryzen 5 7600x
  
• GPU: RX 6700 XT
  
• 32 GB RAM 
  
• Router: Huawei HG8143A5 (PC plugged into the GBit port)
  

Some suspicions/Questions:

• Could my ISP provided Huawei router be the problem? How could I verify this? I could try turning it's bridge mode on and use a beefier router, if its a probable solution.
  
• I can access my home server from outside so the reverse proxy is doing it's job, but how can I verify if my setup is still faulty? Can reverse proxy cause such speed problems?
  

I have to admit, I am quite desperate at this point, all links on google are purple which have my problem and none of those really pushed me in the right direction. I secretly hope my router is the problem because that is the only thing I can not truly test other than buying a new one and see how it rolls with the punches.

Thank you everyone for your time!

[TheDreadPirate]

Can you share your full jellyfin log via pastebin?

[JoeonyJoe]

Hi! Yes of course, here they are from the moment i logged in from my phone remotely:

https://pastebin.com/i2uBqX8V

[JoeonyJoe]

Incredible, I think i fixed it. In transcoding settings "allow subtitle extraction on the fly" was enabled, I just disabled this and im getting performance similar to home streaming! Still, interesting issue.