@rookie7799 - Troll... It is called troubleshooting... Minimizing functionality to the core and see if that works. If not, you have ruled out the other parts of the functionality as the potential culprit.

Nobody said disable it and it will work... The amazing abiility of reading and comprehending texts/posts give one a great advantage so he/she/it does not look like just anotheruseless forum troll...

I'm pretty sure there is a throttling issue on these devices. Anything directly connected through a M9 via hardwire is throttled to 100Mbps. Adjusting QoS lower, throttles lower - to be expected. Any QoS setting above 100Mbps appears to throttle at 100Mbps.

Because the slave M9's connect to the primary, wired or wireless they too appear to be capped at 100Mbps. 

I've rewired around the M9's and get good speeds. An device connected to the primary M9 via wifi also gets good speeds. Swapping the devices primary/slave shows the same issue. 

Interestingly, when I lower the bandwidth in QoS to say 700Mbps, I get 10% of the throughput, meaning throughput is capped at 70Mbps... At 800, 80Mbps... At 1024, 100Mbps. I truly suspect something is wrong with the firmware and how bandwidth is handled. 

During setup I was forced to run a speed test which sets the numbers in the QoS field. I've set QoS as customer with everything on high. Nothing makes a difference with these sections. 

I am seeing same as you see. Speed test in Deco app and speed test with iperf on a wired computer says 700-900mbit/s here, however my iPhone 7 is getting 30 (consistenly, almost like it's capped) on wifi and my macbook gets 250-300 (which is fair I suppose but not impressive). Full strength-bars on all devices. Disabled all of the antivirus and the like. Did a full unplug/plugin of all Decos. Latest firmware.

What's the current status on this? I don't recall this as a problem always (had the Decos for a little under a year now).

Mads

@jubilantjesse Ok Guys I just found a fix for this on my end.  Issue was with QoS.  After the recent update Is when my speed droped on wifi.  The total bandwidth defaulted to a much lower speed after the update.  I ran a new speed test and saved the new total available bandwidth.

This may not be the solution for you all but this was the change after the update on my end.

Running 4 M9 units with Limited Wifi Speed due to QoS throttle default.

Hope this helps.

@Hovercraft - please let me know what exactly did you change in setting. Thank you in advance.

@paraglohiya 

1. open Deco app

2. Tap More tab

3. Under Homecare tap QoS

4. Scroll to the bottom and tap on "Edit" next to Total Bandwidth:

5. Click on "Test"

6. If tested speed is your total ISP output click "Save" an your done.

*Note what the displayed bandwidth is before you edit to see if there is a major change.

This may not be the fix for anyone else, just what worked for me, and I had near identacle symptoms and timing as what I saw from others.

@Hovercraft 

thabk you so much for the quick reply. I will try it now.

@Hovercraft thank you the speed increased from 100 to 310 now. I have set it to manual 1024 limits in QoS for both upload and download.

Original speed from Verizon to my home attaches and another from fast.com showing from Deco to iPhone.

@paraglohiya 

Glad that worked out for you as well.  Is it testing at full speed on the device connected via wifi? 

The update should have forced a re-test of the speed for available bandwidth distribution.