Damn! My A1200's output isn't showing properly on my telly. Wobbly and completely mashed up when anything uses the scan lines just down from top of screen.
Toggling borderblanking changes the behaviour, but not in a usable manner.
Hmm. I'll have to move stuff around, methinks. Maybe reset the screenmode... can't do that through Prefs, can't see any stable picture once the window is open...
I'll need a little time.