Small rolling rocks in rear passenger compartment

Not sure on newer model or what year you have, but my 21 had the rear floor vents wide open, just asking for debris to go inside. Lucky I found some Velcro covers to prevent small items from going in.

Yeah, same. Got a 2022. I think i have to try to pull out the front seats and the carpet one day if possible to try and find the little f@&kers.

My wife’s 23 Y is plagued with a mystery pebble somewhere in the rear footwell also. Occasionally I’ll get lucky when I dump the floor mats and manage to get it out, but it won’t be long before a passenger tracks one back in. Need to get mats with deeper ridges running front to back!! Seriously though, I recall seeing a post awhile back that some lucky guy had a nut or something loose inside his battery pack that he’d hear rolling around. Iirc they replaced his whole pack to fix it. Anyways might want to rule that out too!

From the glass lined tanks of old latrobe.

The noise seems to come from the rear but they are inside the AC vents. Try driving around for a while with the ventilation to the back seats on max. This is how I got mine out. Tesla in my region now tries to push these out by blowing air to the vents from the front. Other than this it's a full, and expensive, dismount. Once you do get them out make sure you buy vent covers, which are very cheap online.

I’ve heard of people who put a loop of duct tape sticky side out and drove around to try and catch whatever is stuck in there. I bought some Velcro covers before I took delivery, and was one of the first things I installed