question for Luxman L-590AX owners


I own the subject amp, have had it for 3-4 years. I recently noticed a low hum or buzz coming from the amp itself (not the speakers), and would swear that it has been dead quiet up until now. You have to have your head right down beside it to hear it. I'd like to hear what other owners have to say. Are your amps completely quiet? Seems like I may have developed an issue. Thanks in advance, and Merry Christmas.
builder3
Haha, erik_squires suggested the same device halfway up the thread.

Dang the whole issue is troublesome though. I was seriously considering targeting an L590axii for my main system and an L550axii for my secondary because I know the SQ is up my alley with my Spendor speakers but now I just don’t know. This doesn’t sound like an isolated incident.

That said, I wonder how prevalent it is? Does it affect 5% of units or 40%? It’s a rhetorical question since probably only Luxman knows and sounds like they’re not talking, also troubling.

Anyway, I’ll continue to follow here and hope that tweak works out for you OP.
If other Luxman class A integrated owners have also experienced the hum, post up!
I know, kren, hard to keep everything straight, lol.
I read about the DC line blocker a bit, sounds like a coin toss. If the transformer has an issue, it's not going to magically eliminate the problem.
I'm not looking for Luxman to come clean on what they know, or don't know, I'd just like a reply on having it repaired. Or, for that matter, a response of any kind.
I'll add this post, for anyone that's interested.
This afternoon I disconnected everything from the amp, my intent being to test it on another circuit. First, I took it downstairs and plugged it in there, mostly because it was on the way to where I was going. No change, still a low hum.
After that, I lugged the thing down to my shop. It's a modern building, 70 years newer than the home, and on a parallel drop with our home service. After the meter, the house and shop are two separate feeds. I shut off every breaker in the shop, other than one 20A circuit that the outlet was on. No lighting, no heat, etc. The amp still had the same hum. I'm not an electrical engineer, so I'm unsure as to how flawed this test might be. Obviously, it eliminates everything in my home. It seems to me that all it really leaves is the initial service from the power company, and the amp itself. I'm still thinking the transformer in the amp.
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snapoli, thanks. I've came to the same conclusion, although certainly nothing that I can prove. Mine's quiet enough that I can't hear it from a couple feet away, and certainly not when there's music playing. It still peeves me, because it's a recent thing with it.
Appreciate everyone's input, thanks.