CTRL + Z stops working all of a sudden???????????
like it says in the title, after a while (usually 5-20 minutes of working in PS CS4 registered version) CTRL + Z keyboard shortcut stops working (instead of doing the usual UNDO it changes image to CMYK mode) as well as ALL OTHER KEYBOARD SHORTCUTS (for example bracket keys [ and ] dont increase/decrease brush size, they just dont do anything).
All of this happens randomly, but never since the beggining of work, always somewhere after 5-20 minutes, probably after a certain operation in Photoshop, applying some filter effects or similar.
Does anyone else have this problem?
Any help is appreciated!
