To use this PreSonus HP4 4-channel headphone amplifier, first make sure you have your own suitable power supply. Connect your audio source to the amplifier and then plug in your headphones. Be aware that the rubber feet are missing, so place it on a stable surface to prevent it from sliding. For maintenance, keep it clean by gently wiping it with a dry cloth. Don't expose it to excessive moisture or heat. If you notice any other issues, consult a professional audio technician.
