I have the exact same issue. It's fine as long as nobody is streaming Netflix or something but the issue is I live in a house with two other people who always stream stuff. I use an ethernet cable, so unfortunately I don't think that's going to fix your problem. My ping sits at around 30 but suddenly spikes up to 100 every 5-10 seconds, basically makes any game unplayable. I've done a lot of research and from what I've seen this seems to be a common problem with BT internet.