The protection circuit is most likely shutting down the amp because of heat. When the amp shuts down, does it feel hot? If not, then further investigation into the protection circuit will be necessary. This is not a problem that is likely to be diagnosed remotely as measurements will be required internally once the amp has stopped working. Check the sepaker wires for shorts that will cause the amp to work extra hard (generating extra heat). Other than that, you will need a servicer to diagnose further.
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The protection circuit is most likely shutting down the amp because of heat. When the amp shuts down, does it feel hot? If not, then further investigation into the protection circuit will be necessary. This is not a problem that is likely to be diagnosed remotely as measurements will be required internally once the amp has stopped working. Check the sepaker wires for shorts that will cause the amp to work extra hard (generating extra heat). Other than that, you will need a servicer to diagnose further.
Dan