Just to add - when I get between 400 and 600mbps down it is “working well” 

Often my download is even slower than that. Strangely my upload is not affected - which makes me assume it is intentional throttling by KPN

Hi @WillemEdeling, welcome! We see this happen from time to time. Generally it is either a problem with the speedtest used, or a problem in the home network. We do cap your bandwidth, but always at a point that is a bit above your contract speed.

So, make sure you use a speedtest that is capable of properly registering these speeds. We see that the Ookla speedtest tends to be most reliable. Also, when you test, make sure you're using a cabled connection. And that there are no other devices actively using the internet. 

If Ookla is still giving you lower than expected numbers, post a screenshot and tell us some more about your home network.

Hi Erik.

This is with ookla.

I've been testing repeatedly with one of two configurations.

1. laptop plugged into modem with cat 5 e cable (short 2m cable) or
2. Laptop plugged in via cable that KPN technician installed.

There is no difference in the results.

I'm usually asked to reset the modem, or worse KPN resets it to factory defaults.

The problem then creeps back.

I.e. I am not complaining about bad wifi performance, but actual internet throughput being severely restricted. Especially download speed being restricted much more.

Check, thank you. @WillemEdeling. Would you please fill in your forum profile and reply when you've done so? I'll take a look and see what I can find.

HI Erik. 

I was out of country for 2 weeks, apologies for the delay. 

Since I have returned the connection has been significantly better. 

I am consistently achieving 920 - 950 mbps both up and down. 

Not sure who changed what - but that you very much. My problem is definitely resolved

No problem, @WillemEdeling. We're not going anywhere :)

I'm very glad to hear the problem seems to have resolved itself. I can't see anything here that seems to have been actively changed for you specifically. So, perhaps there's been maintenance in our network near your node. 

Again, thank you Erik. 

Much better than previous Internet Service Providers I have used. Very happy with KPN