Hi everyone, there's a lot of detail in this message, but I've been doing quite a bit to troubleshoot my problem.

I'm on the 2Degrees Broadband 200/200 UFB plan. I use the FRITZ!Box 3790, with its Wi-FI disabled. I have three Airport Extremes in bridging mode, which I use as 802.11AC access points. We have a decent-sized house, and I find that this configuration gives me good signal strength in most of the house. The Airport Extremes are connected directly to the FRITZ!Box via Cat6 cable, which was professionally installed throughout the house.

Recently, I've had the impression that I may not be getting the full 200/200 I should be getting with 2Degrees Broadband. I've seen a couple of discussions here where people have reported some issues that may point to a glitch in international capacity, so figured it would just sort itself out in time.

This afternoon though, I had some free time, and performed some Speed tests. I was surprised to see that when connecting to the Christchurch Snap Speedtest server, which normally gives me about 200/200, my downstream was anywhere between 40 and about 110. Uploads are just fine, very close to 200.

The first tests were done via the 802.11AC Wi-Fi, which normally gives me the same results as wired Ethernet.
Connecting directly via Ethernet cable to the FRITZ!Box gave me my expected results, IE roughly 200/200. 2Degrees also confirmed my profile is correct, and reset it to be sure.

The obvious conclusion to draw was some sort of Wi-Fi congestion, although that's less likely up on 5 GHZ. To see if that was the issue, I connected an Ethernet cable to the Airport Extreme that is in my office, right next to the FRITZ!Box. This not only ruled out Wi-Fi issues, but also any problems with the longer cabling. I got the same poor results via the Airport Extreme when wired as I did on all the Airport Extremes when on Wi-Fi.

I've restarted all devices.

Last week, I updated to the 6.30 software for the 3790, and I wondered whether the "Green Mode" had been enabled, which slows the speeds of the Ethernet ports. It hadn't.

I saved my settings, restored to factory defaults, and did another speed test with the out of the box settings. The results were still poor when using any of the Airport Extreme devices.

I then followed the instructions to downgrade to the previous version of the firmware, only to find that because 2Degrees has a custom profile on the device, you can't do that. And they tell me there's no way they can help me downgrade.

Interestingly, they told me on the phone that the 6.3 firmware hadn't been officially tested for compatibility yet.

On the face of it, if I can connect via an Ethernet cable to the FRITZ!Box and get the expected speeds, the problem seems to be with the Airport Extremes. But this is happening with three units, which haven't been touched, and where the software hasn't changed since March of this year.

I can't explain why speeds are so poor with the Airport Extremes, wired or wireless, but the next step would seem to be to downgrade the FRITZ!Box if I only could.

If I'm stuck with this speed because I'm unable to downgrade, meaning I can only take full advantage of the 200/200 in my office, then I guess the logical choice is to switch to an ISP like BigPipe that gives me 200/200 without VLAN tagging, so I can take the FRITZ!Box out of the equation entirely and connect one of the Extremes to the ONT.

Any other suggestions very welcome. Thanks. Obviously at this point, I'm wishing I'd left well alone with the firmware.