In c3runtime angle of physical object affects performance

If I set right object's angle to 25 degrees, CPU usage goes to 0.9%, if I set it to 20 degrees, CPU usage goes to 2.4%.

This issue only occurs when using c3runtime, physics and only at certain angles and certain positions.

Any ideas how to solve this? Is it a bug, or is there some logic behind this involving how draw calls work?

https://drive.google.com/open?id=1uAKDYEyTCK6QZduuAks55g8G82PqAgpf