[linux-audio-user] [OT] Block Diagram of a BOSS Digital Delay floor effect needed

Hello list! A little bit off topic, mainly addressed to guitarists or technicians on this list: The guitarist of the band I play with has a weird problem with his floor Digital Delay made by BOSS Roland. As I remember, it is a stereo delay, maybe the 4th version BOSS sold. The foot switch in it behaves not as usual because if the effect is turn on, it does not turn off when you hit it once again. I don´t know if the switch itself is a momentary ( maybe surely it is ) and how it stays in the mode it is ( maybe a simple flipflop ?? ). Does anyone of you know where I can get a circuit diagram of this effect? I found a diagram about my old DX7II really easy in the past, but that´s really old and off topic indeed. Thanks in advance, Marius