I have a sphere dropper instance, but every now and then (most of the time it works fine), the sphere would get stuck in the dropper after the dropper opens up.

It happens even if I changed the instance to a cube dropper.

How do I fix this problem?

Lostprophetpunk wrote:
You could possibly create angled pieces of nodraw or invisible brushes to 'push' the cube or ball out of it.

Wouldn't that block the sphere from dropping in the first place?

Or perhaps you're thinking of creating a trigger that spawns the invisible brush if the cube fails to drop?

I wonder whether there is an easier way.

I also tried the instance "sphere_dropper_norep" or something like that. It worked to avoid the stuck issue, but the sphere doesn't drop straight down as result.

For some reason, this bug has not recurred in the past 24 hours of playtesting.

Perhaps it's just a sun spot interference.