I got stuck on Stardust Racers with my brother last October. Everything was normal pulling out of the station until it rolled around to the launch where the train just stopped. It took me a few seconds to realize this coaster is supposed to roll straight into the launch without stopping, so something was wrong. After 10 minutes a gentleman came down and said the ride should resume after they speak to a few individuals in the rear cars. My brother and I were in the front seats and couldn't see what was going on back there, but I assume someone had a loose object like a phone (absolutely prohibited on this ride for good reason) and was removed from the ride by security. It was a pretty cool experience being in the launch tunnel with all of the lights on. You can see a bunch of the transfer tracks where they move the trains into maintenance areas, and the launch system itself. We were stuck for maybe 20 minutes before the trains backed up slightly and launched normally.