Hi Liam, unfortunately playing on a wireless connection will most likely continue to cause these issues. Black Ops 2 requires a consistent connection - and due to the nature of wireless technology, even the very best connections will experience occasional packet loss - which is enough to cause lag, disconnects, and general headaches playing games online.
Are you able to connect via ethernet cable for testing purposes?
Fixed it by changing my NAT type to open. No thanks to you time wasters lol
Glad you are back in the game - let us know if you need any further assistance. ^NM