I just purchased a used Lexicon MC-1 with the version 1 software. I don't believe there are any defects. Everything seems to be working well except for a low amplitude, high-pitched ringing sound that is emanating from the unit. This sound is emitted while the MC-1 is on or in standby mode. I notice that if I put the front panel leds to 100% the sound is almost completely gone. It's louder when setting the front panel to 25%, 50% or 75%. The sound is similar to that of the Philips Pronto when the backlighting is turned on. (put your ear next to the Pronto and one can hear the noise). Is my MC-1 defective? Has anyone noticed this anomaly with any of the MC-1s or even DC-1s or DC-2s? I'm still waiting for a response from Lexicon (it's been a couple of weeks).