First, ensure the power source to the amplifier assembly is stable and within the recommended voltage range. Check all connections to the amplifier, ensuring they are secure and not corroded. If the issue persists, try resetting the amplifier by powering it off for a few minutes and then powering it back on. If the problem still persists, it may indicate a fault within the amplifier itself, and it may need to be replaced or serviced by a qualified technician.