Found this topic while searching for an answer to the same problem.
The guy I bought the Toccata from sent me three jack converters (4.3mm to two rca)
I'm getting some kind of mono audio from one of the speakers this way. (I'm not sure if the audio is stereo on a single speaker, or only left part of the audio is being carried over through the cable). When I try panning audio,t the following happens:
left: no audio, a low cracking volume.
middle: left speaker
right: sound volume increases on the left speaker
It seems lke one of the channels has a very low volume. Maybe dirty Zorro slot? or faulty capacitor on Toccata?