- 1). Turn off the receiver and allow it to cool for at least 30 minutes before turning it back on if it shuts off. Denon receivers have a protection mode that is in place if there is too much heat. The receiver needs to be kept in a well-ventilated area to avoid it shutting off.
- 2). Plug the receiver back in after it cools and slowly increase the volume. If the receiver shuts off, then it has sustained permanent damage and it will need servicing. If it stays on, then the protection circuit has been reset. Place the receiver in an open area going forward. The receiver can also go into protection mode if the speaker wires contact the back of the receiver instead of the speaker terminal.
- 3). Disconnect the video devices from the video inputs and reconnect them if the video signal is not playing correctly. Verify that the video-out cable is connected correctly to the television. If the wires are damaged, then replace them to avoid any shortages.
- 4). Press the "Surround Mode" button on the front of the receiver panel if only the two front speakers are working. Cycle through the surround sound modes until the right mode is found. Ensure that the surround sound format the receiver uses matches what the connected device is using.
- 5). Check the speaker wires to make sure they are connected to the speaker terminals. Twist any frayed speaker wire endings and replace them if they are damaged. Use banana clips to make sure the wires are properly inserted into the speaker terminals.
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