Quoted from KevinG-ATL:It's got some issues with the upper magnets not releasing. Sometimes one of the balls will drop down into the VUK, but the rest are just "stuck" on the upper orbit magnet.
You need to replace your balls with magnet safe balls. The residual magnetism in the balls will make them stick to the magnet at the top of the game and on the spinning disk.
Had the same problem with mine after I bought the polished chrome balls.