Was previously posted in #1139961574640058448 , but seems more like a bug since another person has the same issue.
Video showcasing issue: https://youtu.be/-HXRQbbrViA
When I'm looking at the setup, all belts are running at 100% efficiency. When I move away and come back several second later, some or all belts are running at 85 to 95% efficiency, which returns to 100% after several seconds.
The setup is theoretically 100% efficient. Four full belts of shapes, four pipes supplied by four pumps each. One belt and one pipe go to four painting machines, for a total of sixteen machines. All upgrades are at the same level.
@sour turret is having the same issue.