1. Repeat the calibration procedure. Make sure that you calibrate at a time when the ambient noise level is at a minimum, and check that you have set the MIN and MAX controls to give you the desired level adjustment range.

2. Disconnect the speakers from the system and, using a microphone preamplifier connected to the speaker(s), listen in headphones to what the 572 “hears” when it is sensing. Listen for any noises, such as air conditioning noise, that could falsely trigger a gain change. Listen for any hum or buzz. Make the necessary adjustments to correct any problems that you discover (reposition sensing speaker, fix or re-route wiring, etc.).

3. If you are using horn speakers, you may be overloading the sense input of the 572. Try disconnecting the amplifier and horn speakers from the FROM AMP and TO SPEAKER CONNECTIONS of the 572. Now connect the LINE OUTPUT of the 572 to the amplifier input, and connect the amplifier output to the speaker inputs. Then, use a single 8-ohm, paper cone speaker as your “sensing speaker”, connecting it to the FROM SPEAKER connection on the 572.