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I'm experiencing a strange issue where my MB-6582 comes up from a cold start and instantly begins cloning it's cores, without me holding down the menu button. Then, once booted, it drops into the oscillator config page and freezes there, completely unresponsive to any buttons or knobs. I assume it's a bad connection or short somewhere in the core1 and/or control surface signal path, so here's what I've tried so far: > completely removed the ICs from U16 - U23 in case they were causing whacky feedback, but no change > exhaustively searched for shorts and bad solder joints all around U1_CORE1 (all seems OK) > multimeter continuity and resistance testing for each socket pin, above and below the base PCB (all continuity seems OK, with resistance levels between .2 -.3 ohms on each pin) > multimeter testing for each core1 component: Designator Description Component type used Notes C1_CORE1 Capacitor - MLCC 33pF OK C2_CORE1 Capacitor - MLCC 33pF OK C3_CORE1 Capacitor - MLCC 100nF OK D1_CORE1 Diode 1N4148 OK Q1_CORE1 Crystal 10MHz 10 Mhz, confirmed with Oscilloscope R1_CORE1 Resistor 100 Ohm 1/4W 1% OK R10_CORE1 Resistor 10K 1/4W 1% OK R12_CORE1 Resistor 1K 1/4W 1% OK R2_CORE1 Resistor 1K 1/4W 1% OK R6_CORE1 Resistor 1.2K 1/4 1% Reads @ 299 Ohms from each core R9_CORE1 Resistor 10K 1/4W 1% OK Appreciate any suggestions or guidance.. Cheers

Not sure what I did to completely mangle my Core 1 and/or SID 1 modules, but both MIDI comms to MIOS and audio are totally skewed now (UHG!).... Starting with the Audio Issue... SID modules #2 - 4 still sound perfectly fine (quick n dirty example below) https://drive.google.com/open?id=1FcfTqcUriYw4KaTXh1OSesTP9RLqs5_i ...But I've somehow managed to destroy the sound coming out of SID module 1?? https://drive.google.com/open?id=1tYVHFEG5-MbfYCJQZLcDfbC6LaOJ9Hk- Here's what I've done so far to try to fix this debacle... 1) Swapped SIDs chips around from other modules, but every SID sounds terrible when plugged into SID module 1 2) Swapped the filter caps (C1_SID1, C2_SID1, C21_SID1, C22_SID1) with brand new, tested 22nf metal film caps (I'm using all 8580R5 SIDs in my build) 3) Swapped the 10uf electrolytic caps that connect to J21 for audio out (C5_SID1 & C25_SID1) 4) Reflowed all joints under the Neutrik Audio out jack at J21 5) Reflowed all the solder joints on both SID sockets for SID1 Mod (U1_SID1 and U2_SID1) 6) Reflowed all the solder joins on the socket for for Core1 Mod (U1_Core1) 7) Burned a brand new PIC and swapped into Core1 ...Nothing has helped, so I'd really appreciate any insight...