wireless card in laptop keeps dissapearing from device manager

Almost every time I come out of hibernation/standby etc my wireless fails to
work, if i check in device manager it has dissaperared the only way to get it
to reload is restart windows, I do have the latest driver, if i tell it to
scan for new changes it finds nothing.

I do have a switch on my laptop and an led to show it is enabled, led is
lit, i have chosen to switch on wireless at boot up from the bios.

Any help much appreciated.