Hiss at addition in system LAMM L2


Hiss (noise) from speakers at addition in system LAMM L2.

Three weeks ago, I have bought preliminary amplifier L2 reference
Improvement in sounding all system was huge!!!! The overall dynamics and scale of the music!!!
Illusion of a presence(finding) in a concert hall has appeared.

But I am disturbed with the following:
At addition in system L2 strong enough noise (hiss) has appeared from
speakers. At inclusion of toggle-switch MUTE hissing disappears, at deenergizing
Toggle-switch MUTE all room is filled with noise (hiss).
Even at listening music on silent passes or piano music
Such noise level it is normal or L2 demands repair?
anton9005
how could u possibly deal with a piece of equipment that introduces a hiss to your system? i dont care how good the soundstage is. i would junk it or sell it. it would be a good idea to let the poor potential buyer know about the issue.
Tvad , I am thinking about lowering the gain on my LL2 Deluxe
If you recall,how much gain in db did you reduce.
Many thanks
ed
Tvad agreed on the loss of transparency with the Rothwells but its the only thing I have found to work to eliminate the AM radio leaking through to the speakers. Shielded cables help but the Rothwells completely eliminate it. Strange as it may sound.
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