Here’s how to replicate the fault:
– Run the Saturn for an hour or more so it becomes nice and toasty. I found that the music player was more than sufficient to do this.
– Next disassemble the Saturn apart while it is still nice and warm and record alongside the power supply (in stereo) to help narrow down which component is at fault.
I suspect either one of the transistors / bridge rectifying diodes or the transformer. I am absolutely in no way an electronics pro though. I can tell you that using a power supply from my both my model 2 Saturns does not cause this to happen. I’d buy the power supplies separately if I could track them down – but they seem to be getting a little rare due to the age of the unit most likely.