I have Ubuntu 14.04. At university I use eduroam wifi and that works fine. At home I use bt hub 6 wifi and that also works fine. However, my friend has a bt hub 4 and the wifi connection keeps "dropping". I can connect to it, it'll work for a while, it'll still be connected but it'll stop working. Sometimes if I keep connected for a while then it starts to work again. I'm not sure how to isolate what is causing the problem.
my wireless card is a qualcomm atheros (QCA6174 802.11ac Wireless Network Adapter)
The BT hub has 2 frequences - 2.4 and 5. both have different ssids and so I dont think it should be a connection issue. I can connect to both and the internet will work momentarily/intermittently on both. If I disconnect and reconnect, it seems to work fine for a while too. Just FYI here's a link to the BT smart hub (https://www.shop.bt.com/learnmore/bt-branded-products-and-services/bt-smart-hub/)