I am having a strange issue with my Mid 2012 Macbook Air. Whenever I connect my external display via Thunderbolt to DVI adapter, my WiFi speed goes from 45mbps to <0.5mbps. The same issue does not occur when I use Thunderbolt to HDMI to connect to TV. In addition to this, I get around 70mbps from the same location on my iPad (right next to router on 100mbps connection) so I am wondering if my WiFi card is going bad or if theres something I can do on the software end of things. Thanks! Edit: Ive changed the external display resolution and I can get 25mbps but its still not what I get without display connected.