Brand new to the world of Mac so sorry if this one has an obvious answer but I cant seem to find it!! I connect my new Mac desktop wirelessly to my ADSL Router which is fine. I sometimes have problems with my ADSL line (latency issues) at which point I flip over to a "3" mobile dongle. Under Windows, I could maintain both connections simultaneously which meant that other computers accessing this machine (for Itunes and file sharing) continued to work fine. On the Mac I find that the moment I connect via the USB dongle my Airport on The Mac disconnects. Is there any way of maintaining both connections at the same time?