Please post back the exact model.
Almost always, for a unit to kick into protect mode indicates that the built-in diagnostics has sensed a hardware fault. This may have been brought about by:
- too high volume level settings;
- speaker problem;
- systems glitch.
Some basic checks/actions that could initially be done:
- check all the speakers. If possible with a continuity tester (DVM/VOM). Speakers should read not lower than 6 ohms;
- verify that the speaker wires are not frayed and the no loose strands that are touching the opposite wire;
- unplug from the mains for an extended period of time. The idea is to force the unit to do a full hard reset and revert back to factory defaults removing all settings, configurations, memory and glitches.
Hope that this be of initial help/idea. Good luck and thank you for using JustAnswer.
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