Yes you understand correctly what I mean by inertia. Just a suggestion. See what others think.
Actually, I see the same phenomenon in my own game which I am working on. It's as if the whole thing skips a frame every 3-4 seconds, so it affects all sprites and is not dependent on how much is going on. I am doing the same as you in my game. i.e: Set a frame rate, and don't use any timers.
If anyone else knows a way round the problem, I would love to hear it.
Actually, I see the same phenomenon in my own game which I am working on. It's as if the whole thing skips a frame every 3-4 seconds, so it affects all sprites and is not dependent on how much is going on. I am doing the same as you in my game. i.e: Set a frame rate, and don't use any timers.
If anyone else knows a way round the problem, I would love to hear it.