JBL LSR4328P Owner's Manual page 45

If you experience any difficulties, go to www.jblpro.com/lsr for the latest information related to the firmware.
Or contact:
JBL Customer Service (Monday through Friday)
8:00am - 5:00pmPacific Coast Time In the U.S.A.
(800) 8JBLPRO (800.852.5776)
www.jblproservice.com