BleepingComputer.com: WIFI Problems after Hibernate or Sleep

Hope someone can help me with this one!

ASUS UL30A - Win 7 64 Home Premium SP1 - Wifi Adapter is Atheros AR9285 - Windows Firewall - MSSE

I have the computer set to hibernate whenever I close the lid, however on re opening the lid WIFI, is more often than not, unavailable (the wifi icon in the task bar has the yellow star over it). Right clicking and selecting 'troubleshoot problems' usually resolves the issue, by resetting the wifi adapter.

This happens whichever Wifi router I am connected to before the hibernate and whichever is available afterwards- home, work, mobile tether, or any other access point.

The problem started about 3 months ago - updating drivers had no effect, neither did last weeks SP1 update.

Driver version is 8.0.0.238 - no updates are available according to Windows.

It happens about 8 times out 10 - very occasionally a full reboot is required, but usually the troubleshoot method works.
Once connected it never loses connection until I close the lid again.

Can anyone suggest a solution? Any ideas appreciated.