In the Demeter's HBP-1 online manual it says, "Warning! do not connect this to mixers with 48+volt phantom power on it will damage the pre-amp." Is this unique to Demeter or is it all pre amps and others just don't warn? I realize just be sure it is off. But I often depend on house sound people and can't always be sure their head is in the game. Often it could be where the sun doesn't shine.