The red light is a power protection circuit designed to shut the amplifier down due to an overload or wiring problem. If the amp was playing then shut off, my guess is a problem with the speakers or the speaker wiring. Some amplifiers are only stable to a certain load. For example, most car audio speakers are 4 ohms which is the resistance placed upon your amplifier to produce a certain volume of sound. If you bridge two 4 ohm speakers together in parallel, you cut the resistance in half, thus increasing the amount of power (and volume) to your speakers. This also creates more heat and could, in effect, shut your amplifier down. I would find out how the speakers are wired to determine the resistance of the load your amplifier is pushing. Also check the grounding.
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The red light is a power protection circuit designed to shut the amplifier down due to an overload or wiring problem. If the amp was playing then shut off, my guess is a problem with the speakers or the speaker wiring. Some amplifiers are only stable to a certain load. For example, most car audio speakers are 4 ohms which is the resistance placed upon your amplifier to produce a certain volume of sound. If you bridge two 4 ohm speakers together in parallel, you cut the resistance in half, thus increasing the amount of power (and volume) to your speakers. This also creates more heat and could, in effect, shut your amplifier down. I would find out how the speakers are wired to determine the resistance of the load your amplifier is pushing. Also check the grounding.