Discussion about the Korg PolySix synthesizer

Hi P6 group,

It unfortunately looks like my power supply is scuppered, and Im fairly sure the issue is with the regulator board, not the transformer though I don't know for sure. It's the earlier revision, so there no test points for the rails on the pcb. 

Basically, I was having a jolly old time making some music as opposed to messing about with a multimeter. I went to make some coffee, came back - no lights on my P6. Turned it off and back on again later to do some testing, alive! Worked for a while then died again. Symptoms were that ALL my rails were dropping. eg. I measured -1.35V or something on my -5V rail, +/-15 were around 4.5V I think. Recently I had found it was sounding a bit distorted especially when using resonance, perhaps unrelated.

Initially I thought something was drawing too much current somewhere, or there was a short because my rails were coming back up again when dropping boards out of circuit (this didn't follow a pattern though). I've subsequently found that what was failing has probably failed. And it looks suspiciously like it might well be the M5330L. 

However, before I take a punt on trying to source one of these chips, I'd like to call on the expertise of the group.... has anyone got any experience with PSU failures in P6's (they seem rare)? 

Could someone confirm what the secondary AC voltage should be from the transformer, and what voltage I should see across the large reservoir caps on the regulator board? Currenty I see just shy of +/- 30V DC there?

Does anyone have an old PSU they swapped out for a Kiwi?

Any suggestions, pointers gratefully received!

Thank you,

Patrick