I am on a 1GBps connection with Hyperoptic connecting directly via ethernet. I had previously been using a Netgear R7000 and had no problems until a few weeks' ago when I noticed upload speeds drop to relatively low levels (around 10-20MBps) while download speeds are fine (up to around 700MBps).
I switched back to the Hyperoptic router (ZTE H298N) and speeds were restored to normal levels (see below):
Hyperoptic Router speed test
So I presumed there was an issue with the Netgear R7000 and bought a new TP-Link AX20 router. Unfortunately this also suffers with low upload speeds:
TP-Link AX20 speed test
The TP-Link router also seems to be unable to pick up an IPv6 address which Netgear R7000 was able to do.
I tried contacting Hyperoptic support but, understandably, they do not support 3rd party routers. For now I have resorted to using the stock Hyperoptic ZTE H298N (without WiFi) and adding the TP-Link AX20 in access point mode so I can at least have WiFi 6, but it would be nice to be able to use the VPN server and more exhaustive LAN features of the TP-Link in router mode. I cannot think it is a CPU issue because it is a brand new router with a quad core Broadcom CPU. Apart from binding IP addresses to MACs on the LAN, I haven't changed any other settings on the TP-Link router. QOS is off. uPNP is off. I could understand a slight drop in speeds with overheads and other processing but dropping off to 20MBps suggests there is something more to it. And I have ruled out the WAN port of the TP-Link as an issue as in access point mode (which runs through the WAN port) it has no issues bridging WiFi at speeds of around 300MBps.
Any ideas on what the issue might be?