Autosweeper is not using its full capacity

[sheaker]

Hello.
I am using autosweeper to perform two task periodically. Task 1, priority 2 is to take one material to one conveyor loader. Then task 2, priority 1 is to move second material to second conveyor loader. Automation is triggered by weight plate set to above 950kg for material 1 (plus some filters and buffers gates to give autosweeper enough time to perform two tasks) and there is near unlimited source of material two. I need rough balance in the system of conveyor belts. Conveyor loaders have 1000kg limits. When automation is triggered usually autosweeper was picking entire 955-965 kg of material one to conveyor loader one and then filling conveyor loader two with 1000kg of material two. But for some reason it does not happened always causing incidental high unbalance breaking the design. I just saw autosweeper taking only 735kg material one (task one) and then taking another 220kg of material one during its second task time.

Why is that? Material one was stacked in single debris and initial temperature of all its pieces was roughly the same. Why autosweeper did no used its full capacity?

Layout + desc:

External conveyor chute drops above 950 of material1 on weight plate activating automation. Weight plate is sending green signal to buffer gate and via 'not gate', closing external conveyor chute. Filter gate is set to 2s just to give time for material1 to fall down and merge with existing debris. Then green signal is reaching autosweeper. As Conveyor Loader 1 (CL1) has higher priority autosweeper is taking material1 to CL1. Green signal from weight plate disappears but buffer gate is granting enough time for autoswwper to perform another task. If everything went well autosweeper is taking 1000kg of material2 to CL2 and just after that the green signal from buffer gate ends, chute opens and cycle is in its initial state.

But if autosweeper did not took entire material1 then second task is just a redo of first task leaving CL2 with no delivery. What am I missing?

Thanks!