Learning more about my 2021 everyday. There has always been the desire, and maybe not necessarily the need, for these hybrid vehicles when functioning on all-electric, cruising in a parking lot say, to make some sort of noise that will alert pedestrians. Can't always trust the drivers to be sufficiently aware of their surroundings. This is not really a complaint, more of a wondering, of how Toyota decided on what kind of noise would get the most attention. They must have had a competition or did some research to come up with the dry alternator bearing sound I currently find my vehicle making when speed drops below 20 mph or in reverse. The volume even varies with speed, getting louder as you approach the 20 mph mark. Probably to alert a larger area. Just a wondering. I didn't do my due diligence and search the threads for similar comments. Thought I would get in a new post which I don't do very often. Now I'll go do my search.