@David-TP 

I have a Netgear GS324 as my network Switch and a Home Hub 3000 (by Sagecom).  

Here's how the network is setup.

- Fiber connected directly to the Home Hub 3000 via an SFT ONT

- LAN port from the Modem connected to the GS324 (Gigabit)

- All DECOs connect via ethernet to the GS324

All cabling is Cat6, even jumbers from Patch pannel to Switch.

As for the frequency is very random.  I tried to isolate specfic times of day, events among other things and for the life of me, nothing is fixing the problem.

My internet is going down, many of my devices, home computer, work computer, TVs, are all wired with Ethernet and don't loose connectivity.  I do have a Mac that's connect Ethernet to one DECOs.  Deco is connected to the GS324 via ethernet as mentioned above, and the MAC is also wired to the 2nd ethernet port on that DECO.  When we loose internet on the DECOs that MAC also looses internet as well, as it's connected to the DECO.

I'm now always (usually) able to access the DECOs via the DECO APP, and I can clearly see all the decos, however all have are not connected to the internet.  I'm able to reboot all and that usually fixes the problem, until the next occurence.

Hoping this helps you.

Jad