If the Rotel integrated amplifier is turning on but there is no output from the speakers, the first thing to check is the connections in your system, and make sure this is not isolated to a specific source by changing inputs.  For example, if there is no sound from the tuner but the CD input plays fine, perhaps the antenna has come loose or has moved to an area of poor reception in the room.

Verify that all speaker wires are properly connected on both ends and none of the wires are touching.

Also, make sure that either the Speakers A or Speakers B (or both) is selected – without these selected the speakers are not active.  If this does not solve the problem your dealer may be able to offer further assistance in troubleshooting your system.