I have used both Dapper(Kde) and Edgy (Kde) - I did experience the problem in edgy but not very often and I didn't realise that it may have been Firefox. I did not upgrade to Feisty, I formatted my drive and did a fresh install. My desktop is now Gnome.
Power Management Preferences:
Put computer to sleep when inactive: Never
Put display to sleep when inactive for: 40 minutes
When power button is pressed: Ask Me
I have used both Dapper(Kde) and Edgy (Kde) - I did experience the problem in edgy but not very often and I didn't realise that it may have been Firefox. I did not upgrade to Feisty, I formatted my drive and did a fresh install. My desktop is now Gnome.
Power Management Preferences:
Put computer to sleep when inactive: Never
Put display to sleep when inactive for: 40 minutes
When power button is pressed: Ask Me
Thanks for your help.