I have a Hifonics zues that has been in storage foe 15 years. An original Zues with the orange lettering before the roman numerals started (3 digit SN). The power supply whines, the frequency is low enough to hear (from the amp not speakers). I can adjust the power supply on the board to silence the sound at idle, but when a small 20k signal is applied it comes back and then it will disapeer at higher signal levels. Does anyone know the recommend procedure for adjusting the power supply. I am a die hard Hifonics fan and want to keep this dinosaur alive.