Strangely enough, I have never run into these issues. As was stated, it may be due to Vulkan. Although I do admit the sound of driving through snow does sound a bit metallic.
Can you tell me where these are? The map is split into different sections that load when you enter another one close to them, but they never reload collision. There shouldn't ever be a collision mesh difference before you enter a section and after you leave it. It could be related to something else. It's either this or no particles. There's no way for me to add a new physics material, but I'll see if I can do something about the sounds.
They were inside the hill right above the mineshaft with the glowing rock, but they disappeared after a bit
