When selecting compact + medium power poles + yellow belts, the final underground output is facing the wrong direction, stopping items from flowing until replaced with the correct direction. Happened twice in maybe 30 hours so not a big deal just reporting anyway.
Is there anything else common between those occurrences? What direction where they placed?
Were those layouts planned with the "Merge belts" option and there's a missing merge belt so it looks like a wrong direction belt?
Are you playing with Space Exploration?