Yes you can limit the speed of the wireless transfer but not the total Broadband speed. Ur Hub 3.0 is b/g/n enabled so u would be able to transfer data upto 130Mbps however changing this interface type to b mode the transfer is restricted upto 30mbps - you can set this either ways
i ) Go to the settings mode in your hub and then go to advanced settings > Wireless settings> Change interface to 802.11b/g/n to 802.11b. click apply ( This may not give u a longer range of use)
ii) Or you could try it on ur PC / Laptop - by accessing ur driver details under advanced settings.
Recommendition : You could take help from BB technical support team (0800 111 4567) 24/7 before you do any changes on your hub.