I'm seeing this all over ranging from my code to SRP and they all share this in common. Can't figure out what triggers it. Our main scene has a test mode where we can just play it and it doesn't trigger there. If I go through our network login that arrives at the exact same scene it triggers fairly reliably on existing playmode. I am using the latest collections which has some new memory management stuff so it could be a bug there that's corrupting memory. Code (csharp): 0x00007FF6E27A2142 (Unity) block_locate_free 0x00007FF6E27A283C (Unity) tlsf_memalign 0x00007FF6DF74C44F (Unity) DynamicHeapAllocator::Allocate 0x00007FF6DF74150A (Unity) DualThreadAllocator<DynamicHeapAllocator>::Allocate Edit: sorry it's not always free that does it. It's still the same at the top of the trace but I've had it hit in deallocate also. Unfortunately last one was a few stack traces ago.