Try increasing the volume and changing to another audio source (if this feature is offered in your model). If the problem persists: * Make sure the power connections are connected properly * Make sure the system is connected to the speakers properly. The copper wires of speakers should be fully inserted into the clips of SPEAKER OUTPUT on the unit. * It is possible that the fuse is blown. In this case, you may need to replace the fuse. Consult the user manual of the system for details.