Years ago when I purchased my Moth Monoblock Power Amps I noticed the LED light on the front of each case was not working. However, I was blown away by the sheer cleaness of sound they produced so I forgot about this niggle for a week or so. Eventually I had the amps shipped back to the manufacturer to replace the existing non functional LEDs with a set that worked. When I got them back and played music through them again I noticed a slight shoutiness/distress in the sound quality when the volume reached 12 o'clock or higher. This flaw was not audible before the amps were sent back, so I assumed that the manufacturer had damaged them in some way. I complained to them via telephone and they assured me they had only replaced the LEDs and nothing else. Still I was bitterly dissapointed and gave the amps to my brother and instead turned to using a cheap Arcam power amp in my system. A few years passed and I took the Moth amps back from my brother to see if the shoutiness had subsided, it hadn't. Then I had the idea of removing the LEDs altogether so I snipped them off at the circuit board. WOW!! the shoutiness dissapeared and my system could now go louder without the distortion or distress it had with the LEDs in place. You see an LED saps on some of the important electrical current from the power supplies of an amp to light it up, resulting in less than optimal sound quality. The result is a slight audible distortion when the volume gets high. Try removing the LEDs on Martin Logans for a slightly cleaner sound also.