@alexp7 

You have PC wired by Ethernet cable to Satellite Deco and it experiences packet loss, is this correct?

If it is, turning off fast roaming and beamforming shouldn't change anything. These are for wirelessly connected devices, and I would suggest to set them back to their defaults (which should be ON).

Things to check for packet loss on PC that is wired to Satellite Deco: quality of link between Satellite and Main Deco, and if Main Deco is overutilized.

1. For quality of link, in Deco app check Signal Source for Satellite Deco to which PC is wired. You can find it in Satellite Deco information page. Example from my Deco:

What does your Satellite Deco show?

2. To check Main Deco utilization, login to Main Deco web interface using its IP address, should be http://192.168.68.1 if you run Deco mesh in its default Router mode. Scroll down to the bottom of the web page and you should see it reporting CPU Load and Memory Usage, in real time. Example:

Wait 10-15 seconds till it settles down, because usually right after login these numbers spike high. When numbers got down and are steady, does CPU run hot? What does Memory Usage show?

Keep that page open in a browser and start your game. When you notice packet loss, check Main Deco CPU Load and Memory Usage again. Does Main Deco run hot?

  @Alexandre. 

I looked into what you said and put everything back to default. 

this is the quality of the link 

and this is what the satellite deco shows when i'm playing

the first picture is during a packet loss spike. in packet loss spikes i could lose between 2 - 20% of packets.

the second picture was taken when there's no packet loss 

my computer cpu doesn't run hot. neither does the main deco or the one in my room

  @alexp7 

Everything seem to be perfect on Deco side. To be honest, I am out of ideas. One of the possibilities is, indeed, failing Deco hardware, but that would be hard to confirm until it fails completely.

The only other thing I can suggest is the following. If you run your Deco mesh in its default Router mode, and it is connected to ISP router, configure Deco mesh to run in Access Point mode. In that mode, Deco provides WiFi signal and does little more, all network and bandwidth management is disabled. How to set up Deco to work in Access Point mode

  @David-TP 

Connecting my computer to the Main Deco would be difficult because my pc is very clunky and would require me to remove my setup. I don't think this is something worth doing.

The packet loss happens to any online game. Packet loss is even noticeable during discord sessions.

The WiFi extender I use is this one: TP-Link AC1750 WiFi Extender (RE450)

Thank you Alex and David for your help on this matter I really appreciate it

  @Alexandre. 

i put my mesh wifi system in Access Point Mode and it resolved the packet issue completely. Everything feels smooth, thanks! If I have another issue I'll go back and reply to this thread. 

One thing I will note though is that when I was updating my game, the update went very slowly. I can try this again another time and give another update because I switched to my WiFi extender the moment I saw the slow download speed (<1 mbps with the Mesh WiFi in Access Point Mode, ~30 mbps with the WiFi extender)

  @alexp7 after a few months my problems have come back but this time the router is on access mode. I;m having constant packet loss during games. It started happening a few days ago. I put the mesh system back to router mode but this caused less frequent packet loss for a longer duration. i don't know what to do. nothing changed,.

  @alexp7 This has been happening to me for months... I regret buying this. I remember I set my deco on access point mode a long ago and it got fixed, but the packet loss just keeps coming back. I've already tried everything, looking in every single post related to packet loss and I just find nothing. Some days it works fine but on many other I have +20% packet loss, which literally makes anyone online game unplayable.

@Miguex @alexp7 

Hey! 
Just thought I'd share my issues and what seems to have solved it for me. I started exp packet loss in games, stutters streaming, general low bandwidth compared to earlier this year. 
I tries everything above that Alex has tried (and had had success with) without a fix to my issues. 
(Even did a clean windows install..)

But when I was setting up my M4's (for the fourth time) I remembered that I had bought 3 + 3 over the years. And saw that they where different versions.. 3pcs was v.1 and 3pcs was v.2.

I'm now only set up with the three that are v.2 and as of now it seems to work. 
Might try to add the v.1's later just to double check it actually was the rootcause.

Hope someone from Tp-link could share some insight to If different versions within a type, cause this issue.