The LOCK error message will appear in the display of the Audio/Video (A/V) receiver when the function buttons or control knobs stop responding. Follow these steps to try to resolve this issue.
- Turn off the power to the A/V receiver.
- Unplug the AC power cord for approximately 30 seconds.
- Plug the AC power cord back in.
- Turn on the power to the A/V receiver.
- Attempt to change functions on the A/V receiver.
If the issue is still unresolved, service may be required.  Go to Product Repair.