Bill jams are commonplace when your kiosk accepts cash payments. No matter how advanced the bill acceptor, there’s always that guy that inserts a bill covered in mud, or something worse, and gums up the device.
Source: blog.kiosksimple.com
Good pointer on EBDS and the Crane/MEI SC bill acceptors for kiosks. Bill Jam is a supported error code for sure. For multiple BAs too I would recommend native COM ports.