For all intents and purposes, my MB-6582 is complete. I have used PSU option A. The PSU itself works properly, everything measures normal. But... I have this huge hum on the audio lines. It gets worse when I connect the fan and is really loud when I use the feedback pots. I've tried mix/matching the two c64 psu's I have. eg: breadboarded to use the AC and DC supply from each and the noise remains. Even used a separate regulated 5v supply. The only thing different in the PSU