Slight humming noise coming from Mark Levinson 331

Thanks for the information! What are my options if my voltage is irregular or over 130 volts?

Hey again, If the voltage is nearing 130v you need to contact your electric company ASAP. Once they come out to check the problem and see that it is high, they'll make the necessary adjustments at the main grid. Unfortunately, if the power is on the high side but still in range (+/- 10%) there maybe nothing they or you can do. The only thing then would be to get a good voltage stabilizer...of course it would need to be able to meet the demands of your current hungry Levinson. It's frustrating, I know, I'm living it. If you are only able to hear the buzz by puttig your ear up to the amp, you are fine. If it is to the point where you walk in the room and can make it out...there are some serious issues. Only other thing you can try is just what the other post says...check the bolt/nut that holds down the transformer. That's about it. FYI, my incoming power is 127v, if I put my ear up to my Levinson no.333 I hear a slight buzz. Before the Elect. CO. corrected the problem the power was 131v and boy was the amp loud!!

One more thing...All of the other amps I was using Krell, Parasound/Halo, Rotel, Sunfire...at 127v, they all buzzed! it's not just the Levinson.

In my equipment ML 331 is very nice and never lsten noise o humming!
Is better that somebody checking his power line at home!

hi Rick, i know it has been over a decade since you had that humming noise in your Mark Levinson 331.  i got the same thing in my 332 amp.  did you ever figure out what the cause of that hum was?