Thanks for posting back with the info I asked for.
From the screenshot you posted your estimate is 3.5Mbps and on your Hub stats you're currently connected at 5.7Mbps. You're achieving a speed higher than the estimate. I completely get that you're experiencing slow speeds but this looks to be own domain as opposed to a network fault. Is it over wireless where you're seeing the slower speed?
Thanks for posting back!
The speed issues you're having look to be more to do with the wireless signal being broadcast from the Hub. The speed to the Hub is exceeding our expectation. Try this link and let me know how you get on: How do I change the wireless channel on my BT Home Hub?