Space Cadet Pinball Game

I think the pinball game that came installed in my HP a1550y desktop has changed, though I haven't played it for months, and I may be wrong about that, but I don't remember it being called "Space Cadet". (Or maybe I just never played it on this relatively new computer.)..

Anyway, whatever its layout on the screen, I have trouble getting started, which I never used to have. When I hit the space bar, the ball rarely springs up far enough to begin its tour of the board, simply bouncing back from the entering gateway (if it even gets that far up the channel in the first place) and resting again at the bottom.

How can I make the ball get through that opening gate to start the game?