Internet drops for few seconds -Weird problem!

Hi, I'm interested if anyone could shed any light on this issue that's tearing my hair out! Have I missed anything?

We have fibre internet 4.5Mbps 35Mbps which is average for our village & good when it works
The Internet goes off between 5 & 130 times per day (over 100 times most days)
The router lights always stay the same (Green) but ALL devices lose internet and stop working. say "No internet" "No signal" etc.

So what we've done;

Swiched off Wifi on Router
Connected LAN cable to ONE PC only - still does it
Replaced Router
Replaced Router again now on 3rd Router - Still the same
Connected LAN cable to ONLY a brand new Laptop (Wifi off) - still the same
Had all extension sockets in the house disconnected
Had Brand new Master socket (Openreach 5C (Mk4)
Fitted brand new cable from Router to Master Socket
Fitted brand new LAN cable to one PC still the same
Unplugged home telephne - still the same
Switched OFF everything in house via distribution board (Heating,Lighting,all sockets apart from Router and 1 PC - still the same
Had 2 x Openreach engineer calls (worked remotely both times, said fixed, but isnt)
Had 1 x Qube engineer visit (said fixed but wasn't)
My Provider logs into my router and it always says "connected" I can see the same my end so they cant ever see the problem.

I have downloaded an extension to Google Chrome called an Internet Connection Monitor it logs every dropout and is consistent with when the devices lose internet it records it correctly. There is no pattern, no particular time and goes off all through the night when nobody using it.

Any ideas gratefully received!
Location King's Lynn, Norfolk, England

Edited by rose123p (Wed 01-Feb-23 11:38:09)

How long (roughly) do these losses last for ?

It says in the title "few seconds".

Power brownouts?
I used to have a problem with this and I bought a small UPS to get around the issue. It seemed the router was very susceptible to a small drop is voltage. No other items in the house were affected.
The UPS sent an email when this occurred and it only lasted a few seconds or less.
More recently it has stopped so I think the recent work on our small sub station has fixed the issue.

Fair point.

If it is just for a ‘few seconds’ then the router isn’t losing sync. It cannot drop sync, re-sync, then authenticate in just a few seconds.

Not sure if the Chrome extension can support this, but you need to monitor your connectivity to the internal IP address of the Sky router, and then something on the internet.

The other thing that might be worth trying is disabling IPv6 on one of your PCs and seeing if that acts differently to other devices.

thanks to all of you that took the time to reply ffolks!

So a major update:

Friday a Broadband engineer was working nearby up a pole, my wife asked him if he was looking at our issue, he said no but this amazing guy took the time to ask about our issue, he very kindly offered to pop over and do a few checks (this is something weve asked our provider for since August 22)! Within 5 mins he found the FEC rate was ridiculously high (110,000 in 3 mins)

He's then gone to a connector 100m away and plugged in there - down to 40 FEC's in the same time period. I then remembered we had an outage some time ago where workmen had put a digger through the cables, BB went off for 5 days and has been temperamental ever since. This was between our house and his test point. So we think there is a cable issue uderground.

I've since found in "diagnostics" in the router a secrtion where it shows you the FEC's, yesterday was over 35 million! (35533378) downstream and just 205 upsstream.

I'm just waiting for my provider to come back to me tomorrow to tell me again theres nothing wrong and I'll then explain this to them.

Thanks again and I'll post up what the fix definitely was when its sorted

FECs aren't the issue, it's CRCs. FECs are errors which never occurred

Can you view CRC errors (might be able to find loss of link / number of drops which is useful else failing that is there a broadband uptime or a WAN uptime) which isp? Which router?

I disagree.

When FEC’s are high enough, the usage can appear slow. The router will eventually drop sync looking for a better signal.