Virgin Superhub 2ac latency (picture included).

Someone walking though the room ?

It takes almost nothing to cause data errors in wireless signals. They are then retransmitted until a clean copy is obtained. This takes some time to do which is why you see spikes like this in the data.

There are many many devices that use the same radio frequencies from cordless phones to security cameras. Most phones and tablet are constantly sending some amount of data into the various WiFi radio bands. Any one of these can cause a spike like that.

Its just one of those things you have to learn to accept when you use wireless. It is not like a wired connection that you can send data constantly for days at full speed and maybe get 1 or 2 errors.
 
I'm getting ping spikes of 60, 100 and sometimes 400 to my gateway on my 5Ghz network. Last night it was consistently over 100, now it's mostly around 1-2 except when it spikes.

Ping spikes of 15? I DREAM of ping spikes of 15! 😛