Buggy Network Manager

I have an HP dv6000 series laptop and when I’m using my wireless (Atheros 242x pci card)It randomly disassociates me with the access point and the only way to get it working again is to reboot the computer. Then about 5min later it drops my connection again. The AP is using no security because it is an open network. Any Ideas on what might be wrong?

Cheers