Hittade detta:
1. Go to Preferences-->Network
2. Add a new location
3. In the Show: menu, go to Network Port Configurations
4. Make sure AirPort is checked (it probably is)
5. Drag Airport to the top of the list (above Modem)
6. Click Apply and watch your signal meter. In about a second, it'll pop back to life.
På "Add new location" skrev jag namnet på mitt wlan.
Verkar hittills funka.