Intermittent connection issues loading/changing site- secure connection failed/site can't be reached

[EDIflyer]

Is anyone else occasionally getting a 'connection down' error from Chrome (or 'Secure Connection Failed' from Firefox) when changing page - if I hit refresh it works fine. At first I wondered if it was the site I was using but have noticed it on multiple different major websites over the past couple of months and not noticed it from other locations where I don't use Three Broadband so does seem to be related to the router/connection (this is via wired Ethernet too, so not a WiFi problem).  I've tried changing DNS server in case that helps but no difference.

It mainly seems to happen when trying to first load a site or (annoyingly) at checkout when a different site is being loaded as part of the checkout process.  It certainly doesn't happen everytime but does happen with reasonable frequency.  I've also noticed I often get it when trying to pull/push from/to Github too and have to do so a number of times for it to work (browsing the Github website works fine).

I'm using a NR5103E with Firmware Version V1.00(ACBJ.0)b14 - I tried rebooting it but to no effect.

[bytespider]

Can confirm, disabling all IPV6 features does not help.

[EDIflyer]

Yep, I tried that a few months ago to no avail.  Having more issues with my smart TV recently @JonathanB can we have another update please? Surely given the number of customers being affected this is being looked at in depth and there should be weekly progress reports to senior management?

[AkiTaiyo]

Must also note that just changing DNS doesn't mean the problem goes away, theres nothing to say the resolver wont give you the failing location at some point in the future..

[AkiTaiyo]

Well, I've wasted more than enough time on support calls with people that just follow the same script over and over again, "reset the router", "the problem is with the app", "is the 5g light on"..

Time to change provider.

[AkiTaiyo]

On the plus side, it looks like I can get out of my contract without any early leaving charges..

[AkiTaiyo]

Here's an odd one, might be worth trying if you can..
I moved the antenna (I use an external antenna) yesterday to improve my EE reception.. As a result my 3 signal dropped a bit (router does dual sim).. Now getting about 250/18Mbps (down/up) average compared to the previous 400/35.. But using Three internet today with a lot of Microsoft and Azure services, no 'End of file' errors, even with my original DNS settings..
Could still be coincidence though..

[AlSeek]

I have found setting the router in 4G only mode results in the error appearing less frequently than when in 5G mode, potentially could be related to the reduced speeds of 4G. Who knows ¯\_(ツ)_/¯
It does still happen in 4G mode though.

[AkiTaiyo]

Yep, was purely coincidence that I'd had a day without error.. about an hour after writing that post, back to errors again.

[bytespider]

I took get days where I think all is good and others where every other request gets EOF

[robjames_1]

I got in touch with three via live chat tonight to cancel my contract following months of this issue. I was offered a replacement hub which I’ve decided to try out. Currently using a huawei h122-373. It’s arriving Wednesday so will update at that point to see if it’s made a difference. If not then I just need to wait for the 17th when my plusnet contract starts!