After powering on, my microbrute se makes strange noises and a few of the lights light up (the center octave light and the envelope light). After about a minute, the noises and lights die down. Here is a sample of the noise: http://vocaroo.com/i/s0olCvfOkiKB
I have not done the firmware update (but I bought it used, so it could have had it). I haven't used it for a few months, and the one time I transported it, it was in the travel bag.
Could this be a power supply issue? Or something ??
After typing this I switched to High Pass Filter and it started making horrible noises: http://vocaroo.com/i/s0Hv5xSPai2N