Sorter slowing down tier 3 belt

Describe the issue
I found a sorter causing bottleneck on my tier 3 U-shaped conveyer belt. Throughput seems to be halved after going through the sorter.

Expected behavior
Sorter should not bottleneck the tier 3 belt when there is no backing up at both output ports.

To Reproduce
Steps to reproduce the behavior:

1. Load attached save
2. The problem can be seen at the sorter array of loose storage (with tier 3 belts) next to the farms at the elevated area.

Additional context
Version 0.4.6
I have tried rebuilding the sorter and attaching one segment of tier 3 belt at the filter output (instead of connecting directly), the problem remains.

Attachments
Save file:
issue report.save

Video in discord
https://discord.com/channels/803508556325584926/883590993063051275/992027183960829952

Similar issue has been reported by Paa#8247 at Discord, with a video in the #message
https://discord.com/channels/803508556325584926/883590993063051275/991979319914135592

Files not imported: issue report.save

Confirmed in my own save.

Would think sorters and balancers had unlimited speed internally.

I had to use contraptions like this to not clog up everything behind it:

save_22-07-26_23-20-41 U-shape sorter is not unlimited speed.save

COI 0.4.8

Files not imported: save_22-07-26_23-20-41 U-shape sorter is not unlimited speed.save

Or maybe not have unlimited internal speed, since it can then be abused with 1 belt -> 1 sorter -> repeat. Maybe copy belt/pipe speed on incoming speed and use it internally in the sorter.

Thanks for report, this was fixed in v0.4.9