I have trouble with A1200 Lyra 2 also, but I always thought it's because I'm using it on an A500. After reading about your problems I'm not so sure anymore. When I return back to Workbench after playing some WHDLoad game, a single key press then produces multiple characters eg. if I press the c key I get about 4 of them. I need to soft reset the Amiga to get it working again. So maybe there are incompatibilities.