kde 4.1 random shortcut fail

hi, using opensuse 11 kde 4.1 im randomly having problem with shortcut
sometimes when i press alt-tab and others it just do nothing… my guess is because of konsole i run konsole maximized all desktop but not sure if thats the problem

I have the same problem with openSUSE 11 and KDE 4.0.4, even without running konsole at all. Every now and then Alt-Tab simply does absolutely nothing at all.