[gb160]

I'm using an app called Network Speed. How do I use iperf?    

Im probably stating the obvious here but make sure the wifi isn't still connected on your firestick.
https://forum.kodi.tv/showthread.php?tid...pid2796340

I was planning on getting the ethernet adapter once Amazon fix the 1080i problems (which thankfully it finally looks quite promising), but I dont think I'll bother if there are issues.

Should note that @noggin was doing these tests back in 2018 so god knows if something has changed since then.
It would be good if someone could perform an iperf test on the current firmware and share their results to see if anything has changed.       

Where do you see that they will fix 1080i? Any public record available that they commited it?      

All I know is from this long running GitHub issue:

https://github.com/amzn/exoplayer-amazon-port/issues/94

If you go quite close to the bottom of it an Amazon dev has asked for loads of samples of video files that were causing the player to crash, these were his findings:

Thank you guys for the links and for your patience!
The latest firmware we received from the vendor had issue playing only one of the files listed above. We are discussing the leftover issue with them to get to a point that all files listed play to the end. There still will be garbled frames at the beginning of some files as not all of them start with a full I-frame and necessary headers. The current focus is on stability of the decoder.
Sorry for being vague, I am legally required to not state anything that is outside the direct influence of my team.

He goes on to say that the proposed firmware from the vendor 'should' be pushed out to users in Amazon's Q2 update, which is sometime in Apr-Jun.

I provided quite a few links to problematic recordings taken from TVHeadend using DVB-T2 for 1080i Freeview UK Channels, and he said that the proposed firmware plays them all with no issues.
Quite a few other users posted problematic samples as well.

The Amazon dev is @zsmatyas on GitHub.

I might be being naive here but this sounds promising to me...thoughts?