@Dutchbear80 

all internet connection is lost, that's correct, ziggo confirms the router can no longer be accessed by them when this happens.

The deco units themselves remain working normally, except ofcourse they no longer get internet from the router.

I can reproduce this fairly relliably, as in, if i connect every device by WiFi only, incl the ps5 pro, this doesn't happen.

As soon as I cable the ps5 pro to the deco, it will lose connection, not straight away but I happens guaranteed.

The strangest part is, it also happened when all devices (nighttime) were turned off.

Where the only commonality is the fact I got that ps5 pro hooked up by cable. (But I don't use rest mode)

So either it's the ps5 pro in combination with the deco and/or firmware creating either a network storm or network loop somehow.. or.. I'm completely at a loss.

Ziggo has agreed to send what they call an "escalation" uh.. mechanic? Repairguy? You know what I mean.

Just keep in mind everything worked flawlessly for literally years, until right after this firmware got installed.

  @David-TP 

As far as I know, 165 cannot be rolled back once installed, at least that's the warning it gave before I installed it at the time.

This is different if someone uses lets say a laptop or whatever, connect it directly to the deco and install an older version that way?

  @David-TP 

to reply after further investigation.

Ive ruled out cable issues, I've further installed a third m4R unit (I forgot I still had it) never used, updated this to latest firmware, same problems.

Ive tested and swapped out decos, different ports for different cables etc, nothing works.

I have also made a guest network on the deco's, plus set the ps5 pro to only use 5ghz for stability sake. (Instead of automatic 6ghz, 2.4/5ghz)

I have narrowed it down to either this type of deco, the specific firmware and ziggo routers, combined with PS5 (pro), this seems to cause a problem with multicast network activity.

This problem didn't exist before in older firmware, you need to look at this on your end if possible.

For example a guaranteed network crash is ps5 pro, Crunchyroll (which is a heavy multicast traffic app).

However if I use YouTube, it doesn't happen.

The problem seems to be how these decos now communicate with the router, overloads it and causes the internet to cut out.

The router doesn't show this at all (white light keeps on normally) which heavily suggests the interaction between deco, ps5 pro and this type of router is suddenly a problem since 165 firmware.

the ziggo router in question is a black smartwifi router. (Sagemcom)

considering the m4R units are heavily used and still sold by ziggo, I think this warrants further investigation.

edit * tomorrow i will install X50 decos to see if that makes a difference, brand new.

if im right, it should make a difference, different firmware, better specs plus much better hardware/Ax3000 protocol, so things like multicast should effect it far less.

  @David-TP 

Its going to take some further testing, but I have successfully rolled back to firmware 162.

So far, all problems have vanished.

I feel confident to say, there is a problem with 165, the m4R versions in certain software/configurations, as I've ruled out all other hardware possibilities like cables, certain devices etc.

Perhaps some ARP/DHCP problem the router experiences, or MAC addresses that get spammed, multicast streaming apps like Netflix/crunchyroll or I don't know what exactly, but something is going wrong with ziggo, m4R and 165 firmware under certain conditions.

  @David-TP 

okay sadly, I still dropped connection from the router with 162 installed, it's somehow the ps5 pro causing this, I have no idea what else could do it.

im going to install the x50 decos later tonight, hopefully this will help.

Seems like installing the x50 decos have stabilized things. Still not sure what went wrong on the m4's.

But I haven't experienced any drop out of internet, yet*.