I just bought the Musical Fidelity A5.5 integrated, and am really enjoying listening to it--with the extra power and dynamics compared to my old integrated (the Pathos Classic One). However, I couldn't help noticing an audible hum coming from the transformer area of the unit (front left corner). It is not loud (and not audible while music is playing), but it is audible during silences. Is this normal for this integrated, or is there something wrong with it? I have never heard a hum like this with any of my other gear before, and don't know what to make of it. I hear the hum either with, or without using a PS Audio Quintessense filter. I've tried different outlets in my house, and even disconneted (and unplugged) the CD player, as well as the speakers without affecting the hum. Am I being too sensitive, or should I send the unit back on warranty? Please, anyone who owns or has listened to this integrated, let me know your experience.--Unklechukar