Repeated packet loss, high latency, loss of Internet connectivity

[Uberseehandel]

I've has a fixed mobile broadband connection for a couple of years. It's performance gets worse over time.

page after page of crap like this -

Internet connection WAN1 (BT) on port 3 is restored.  Today at 10:05

Internet connection WAN1 (BT) on port 3 is experiencing packet loss.  Today at 10:04

Internet connection WAN1 (BT) on port 3 is experiencing high latency.  Today at 06:24

Internet connection WAN1 (BT) on port 3 is experiencing high latency.  May 28, 2025, 05:20

Internet connection WAN1 (BT) on port 3 is restored after a temporary disconnection.  May 27, 2025, 05:15

Internet connection WAN1 (BT) on port 3 went down multiple times in the last 24 hours.  May 26, 2025, 14:17

Internet connection WAN1 (BT) on port 3 is experiencing packet loss.  May 26, 2025, 09:09

Internet connection WAN1 (BT) on port 3 is experiencing high latency.  May 26, 2025, 06:51

At the best of times, latency remains high and Internet speedtests show an alarming decline in both upload and download speeds.
Finally CGNAT (Carrier Grade NAT) is an appalling concept that should never have been adopted by a carrier that values its reputation.
I have direct line of site to the 5G cell 110 metres away.

What are my alternatives?

[ArmitageShanks]

It seems likely to me that you're suffering the same issue that affected me. The workaround that I implemented is working reliably after a couple of days. With a try for you? https://community.ee.co.uk/t5/Mobile-Broadband/Barely-usable-internet-for-about-a-week/td-p/1537115

[Uberseehandel]

Thank you for suggesting that.
Unfortunately, my EE supplied and preconfigured router (Zyxel Nebula FWA510 5G) has been locked and switching from the default
Auto (4G/5G) to 5G SA takes the router offline. Internet connectivity is restored immediately I revert to Auto(4G/5G).

I suspect a lot more digging will be required.

[ArmitageShanks]

The workaround for me wasn't too do anything with 4G versus 5G. Rather, it was too so it using IPv6 and force it to use IPv4 for the mobile, as opposed to LAN, side of the router. I had to select IPv4 for "PDP type". I think EE have recently broken their internal IPv6 implementation. If your router offers an equivalent setting, I recommend you give it a try.

[ArmitageShanks]

Page 72 of this page implies you might have an equivalent setting on your device: https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://download.zyxel.com/Nebula_...

[Uberseehandel]

I have tried to do that, in the past. Unfortunately, the EE supplied router has been nailed down, so those options are not available. I spoke to support about using IPv4/IPv6 and they were horrified at the thought. Fortunately I don't play games. If matters continue as they are, I'm going to die of boredom waiting for web pages to load properly.

[ArmitageShanks]

Maybe demand they send you a router that allows you to disable IPv6 if they want to retain your custom?

[Rach_H]

Hi @Uberseehandel,

Welcome to the Community!

I'm sorry to hear about the trouble you're having with your connection. Have you spoken with our team about the issues you're having?

Rach

[Uberseehandel]

Good thought, first I'll follow up on Rach_H's intervention😀

[Uberseehandel]

@Rach_H 

Thanks for getting in touch.
I have have previously spoken to support folk. I'll get in touch with them again. Following what @ArmitageShanks  managed to do, it seems I need a router that is  fully configurable.