Item falling through floor - edge case

Hi - I thought I solved this before but I haven’t and I’m wondering now if it’s a bug. I’m using UE5.

My character can drop items. My items are physics assets so they fall naturally to the floor. My items are not super small i.e. rifle, hammer etc. Occasionally, (probably 3% of the time) they fall through the landscape floor. My landscape collision thickness is at 32. My items all have one simple box collider on each of them. I’ve also turned CCD on to them too. They are also not dropped near the floor, they are dropped about a meter above it.

It’s not often and hard to reproduce but I can’t figure out why they fall through the floor just a small % of the time. It obviously breaks the game even if it happens once. Is this a bug, or is there something that could be causing this?? Any ideas on how to fix?


Im having a similar issue atm. My ball falls through the ground 50% of the time. its super reproducable. ccd causes the ball to stick to ground for 5 seconds or so.

Im hugely interested if you get a response.