On a G5 Quad running 10.4.6

When I press a key a 'scrabble tile' appears in the top left of the primary monitor with the key legend and catalyst function (e.g Q Catalyst HUD off) in the row order of the keys

When the key is released it is replaced by a thin rectangle

This happens on catlyst v4 and v3.

On my previous set up (10.4.4 catalyst v31h20) This would happen occasionally but I couldnt work out what caused it. I just restarted the program and the problem went away.

Since upgrading to 10.4.6 it happens nearly all the time.