I have connected a composite / S-video out to my TV but I can't see the receiver's on-screen setup menu.
The On-Screen menu is available only on the composite and S-video outputs that are labeled "Monitor Out" (or "Mon Out"). Please verify that the composite or S-video cable is connected to the appropriate monitor output connection on the rear panel of the Rotel component. Also verify that the TV is on the correct input as well. Make sure the Rotel remote control is in the AUD mode by pressing the "AUD" button. Then press the Menu/OSD button to activate the on screen menu.
A simple test to verify that the physical connections from the Rotel component to the TV are correct would be to power cycle the Rotel component. When the unit first powers up, a "System Status" screen should appear on the TV for a few seconds, then disappear. If this screen appears, the connections are correct.