I had two buses set up as ai chasing me. I turned them off and was just driving around with another car and was curious where this one went too. So I switched over to it to find, to my amazement, that the thing was making music on its own. I wasn't touching any buttons besides my camera controls which don't interfere with any vehicle controls and the ai was off. It'd switch from reverse to drive on its own, adding to the self made music. -------- Then there's the Goat. It's amazing what you can find on the mod section on the forums. It may be dated old, but it still works hahaha
