Playback Stuttering on Fire Stick

[SteveSharpe]

I am having some issues lately with playback on certain Fire TV devices.  The video will freeze for a few seconds and then resume playing.  Some days it seems to happen a lot, other days not at all.  It doesn't seem to be specific videos and these are not complex videos (most are 1080p h264 without any super high-end audio channels).  They all are Direct Play on the Fire TV devices.

I've been trying to troubleshoot but I have to wait for the random days it starts happening as it is not a regular occurrence.  The videos are all Direct Play so I don't think this is a transcoding problem.  When the issues start to happen I check the server utilization and it is very low.  No CPU spikes, no reported issues with disks, and plenty of free RAM.  I can post Jellyfin logs from the next time it happens, but in previous times the logs haven't contained any errors on the server side.  It seems as if this is a client issue and Jellyfin thinks the video is playing away just fine.

I've tried switching between LibVLC and Exoplayer, tried changing to different audio tracks, etc.  Doesn't seem to change anything.

I've had Jellyfin running for about a year now.  A few months back this started happening and I thought maybe it was the old server running weak hardware.  I rebuilt the server and for a while after I didn't get the issue so I thought the more powerful server was the fix.  But it seems to have started happening a lot again lately.  I am not certain if there was a recent Fire TV app update.

I am currently running Jellyfin for Android TV version 0.15.12 and the server is version 10.8.10 running inside a Docker container.  The issue does not happen if I watch the same videos on a PC in a browser and it actually never happens on my really old Fire sticks.  Seems only on the newer Fire TV 4k devices.

I guess I'm looking for two things.  One, has anyone seen similar behavior before on Fire stick or other Android TV type devices?  And, two, some advice on how I can better troubleshoot this when it happens again.  The logs haven't been too helpful and the wireless connection seems alright every time.  Maybe there are some client side logs that can be gotten?

[bitmap]

Do you have much network interference where you live? I'm guessing the sticks have pretty weak wifi chips in them and if you're on standard channels, that may cause issues if you're bumping up against neighbors. Or if you have a neighbor who thought they were smart by swapping to overlapping channels, that can be insanely destructive to your signal quality.

Logs would be helpful, but with direct play, my first instinct is always bandwidth/network strength/quality, particularly when you're looking at wifi devices.

[SteveSharpe]

I don't have any wireless interference with neighbors and I have my multiple AP set up pretty well without channel interference in the house. I am a network engineer so I think this part might be okay but I will do some testing to see if for whatever reason I am getting dropped packets.

The odd things to me are that it seems to only be the stronger Fire Stick 4k that are having issues and it also seems to be random times it happens. I'll dig deeper on the network and client side. Might even move these fire sticks around to see if they perform different in different rooms.

[SteveSharpe]

Posting on an old thread to give an answer as to what I found in case anyone finds this in a search. Bitmap was correct in that the issue ended up being Wifi related. It was difficult to track it down because the device would bounce around between APs, but it did end up being network issues in the end. The Fire Stick was in a TV stand and I suppose due to the walls of the stand it would often switch to another AP that's further away. When that happened the network speeds would drop too low to maintain playback on high-quality videos. I repositioned the stick such that it will always stay connected to the closer AP and everything has been fine since.