I recently mounted all the components in the PCB (with the +/-15V mod) according to the specs. surprisingly I become a very strange kind of sine wave -like a cheap synth- in intervals (used two differents 9v PS), even with the input cable disconnected. Of course I can add pictures later if soemone is around and curious. Had anyone experienced such anomaly? Thanks in advance!
Ariosto
Post some pictures of the top and bottom of the board. That'll give us a place to start. I'll check mine, I think I built the 15v version and no issues.