Got the M4's as well and doing video calls is just a nightmare. I get stutters and complete freezes at least five times in a 30 minute call. Also noticing the 100% spike. Might have to return these and revert back to my old Airport Extreme mesh solution which gave me slightly slower speeds but at least a constant connection.

@pedrohsoaresbr 

For probably 12 months now it's become an office joke where I constantly struggle with MS Teams video, vpn drops etc - never had this issue before the M4's. Cannot believe it's been a year of struggling - and my fancy new Deco's are to blame! Also running constant high CPU. Recommended them for easy install to another friend who runs home cinema, streaming high quality from a NAS - completely unusable - video stuttering etc -the moment he removes the deco as the router, things return to normal.

Using the M4R as a router (Main unit) - and additional AP. Guess have to dig out that old router and see if it helps - but feel this is a design issue as the CPU's are too slow.

I'm here having the same exact issue with my deco M4R's v2 ___ 1.4.3 Build 20200918 Rel. 74289

I set one of them as a router and connected a switch to it to feed my other 4 deco's via ethernet cables and i'm getting 100% CPU use almost all of the time on the main deco (router) and even the other units, I also tried to set them as access point's only with the main router tp link ac1900 v3 but i'm still getting CPU spikes to 100% on all the deco units.

I think this is a hardware limitation because sometimes I can't even open the webUI its not loading or if change something in the settings it tells me that the (operation failed). 

I have the M4 with 2 nodes like most.  CPU utilization has been 100% for a long time.  I have noticed that performance of the Deco has been sub-par and even bad at times lately.  We have around 15 devices in our house connected to our Deco system.  Throughput is all over the place.  I initially thought that the cause could be the monthly logs, so I turned that off.  It did not remedy the high CPU usage or performance.  I then began to disable internet access to one profile at a time to see if I had a device that might be flooding my network with packets.  That wasn't it either.  I ran wireshark grabbing ARP/RARP requests and didn't see anything that stood out.  I took the Deco out of the mix and plugged my older ASUS (Linux kernel) in and ran the same tests.  Throughput was perfect and where it should be.  CPU load with the ASUS router back in the mix never exceeded 40% on that router.  

There is an issue with something in either the hardware or the firmware for this particular M4 Deco.  If TP-Link doesn't address this soon I'm tossing this in the trash.  As a point for anyone looking for something else I suggest you look for Ubiquiti.  By far some of the best equipment on the market for the price.  

@meyouthis That's a good point that I left out in what I posted.  The webui is almost unusable.  I get the "Operation Failed" message a lot when I'm attempting to do something utilizing that route.  

@TP-Link 

Finally you hit a knock! The entire thread is complaining about poor Deco's performance and high cpu utilization. Does Tplink has an idea about that? Or we just should look away to other solutions?

I hope we will get an answer quite soon about Tplink....

Regards.

@TP-Link 

The Deco M4 sits behind a Netgear Genie DOCSIS 3 Cable modem, Non-NAT.  

TP Link ID is turbodsc@gmail.com

M4 Firmware Ver.: 1.4.3 Build 20200918 Rel. 74289

Deco M3W Firmware Ver.: 1.0.7 Build 20210106 Rel. 65893

As to your question about performance during high CPU utilization, it is everything you listed.  Throughput, Web UI, and connectivity up/down.  We have 50MB symmetrical Cable internet.  My Asus RT-N66U doesn't have any issues when I switched back to this router.  The only reason I purchased the Deco mesh was to provide better coverage throughout our house.  It's hard for one router to cover 3,500 sq/ft.  When we first unboxed the Deco it seemed to do a good job and it wasn't until more recently that this has become an issue.  My guess is something in one of your last 2 or 3 firmware updates has experienced an undocumented feature.  :-)

I have the same issues with CPU 100% and poor connectivity.

I use three E4R(1.0) and three M4R(1.0) with one of the M4Rs set up as the main router. 

Experiencing issues since last firmware upgrade.

I have the same issue of high CPU spikes however I'm not 100% sure that its impacting performance. I ran a quick ping test and no packet loss. However working in the industry any device spiking to 100% CPU regularly is not a good sign and i will monitor this situation clsoely and follow up with any results.