My unit says over load shut off power and turns off 2nd set of speakers???

Check speaker impedance! If not compatible disconnect.

Here are some things toy can check and try.


Connection faults
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Check the speaker cables for shorts or damage. Crossing speaker wires can destroy receivers.

Some units are sensitive to speaker polarity problems. Make sure both sets of speaker cables have the correct polarity.

Very thick, or otherwise incorrect speaker cables can also cause faults like this. Try thinner wire if you are using very thick wires.

You may have the wrong speakers. Check the resistance the unit expects (usually 4 or 8 ohms), and make sure it matches. Try different speakers.

Could be other speaker faults. Some active speakers can develop faults, or there may be an internal fault in the speakers. Try different speakers.






Thermal overload:
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As a general rule, don't run the second set of speakers if you don't need them - usually runningthem will degrade audio quality, increase power consumption, and increase the liklihood of thermal overload.

Try listening on a lower volume, see if it still does it. I have a unit that behaves this way mostly in summer when it is warm. If it does not do it when the volume is low, that's an indicator it may be thermal overload.

Check clearances. Don't block vents or place the unit in an enclosed space. Check the manual for a guide.

Check for dust, you might need to open it, (This will void the warranty if any, and can be dangerous even if the power is disconnected). You may use an air blower (like in a can) to clear the dust - or carefully use a vacuum cleaner).

If you suspect thermal overload, try pointing a domestic fan at the unit and see if it still does it.



Internal fault
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Sometimes faults in the unit can cause these sort of symptoms. I've seem problems with volume knobs, and other parts. You'll need a proper service agent to investigate if this is suspected.