Make certain that each ouput channel from the unit is driving no more that 4 ohms each. If you have more than one speaker attached to an output then be sure they are wired in series NOT parallel. Two 4 ohm speakers in series is an 8 ohm load and the same two speakers in parallel is a 2 ohm load. If the speakers are dual voice coils then you must treat each voice coil as if it were another speaker when it comes to wiring.
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