Roland SP-303 problem, service manual needed

[technicalspecialist]

I run my own electronics repair business and I have a customer's Boss SP-303 Dr. Sample on the bench.
I've been playing samples and playing around with the effects for a while.
The problem is that it randomly freezes/crashes, can take a few seconds after power on or many minutes. Doesn't matter what I do, its completely random.
I have to switch it off/on to recover it. I have looked over both PCBs and they're ok. Can't see any cracks. None of the capacitors are bulging, no diodes, transistors overheated or shorted.
I am powering it from my variable bench PSU at exactly 9VDC. It draws about 0.25A
I need the schematic diagram/service manual. If anyone has one, please could you PM me.

[technicalspecialist]

Re: Roland SP-303 problem, service manual needed

Its ok now, I emailed Roland and they sent me the service manual.

[Longbow]

Re: Roland SP-303 problem, service manual needed

Let us know how your troubleshooting goes on this problem. If the crashes are really random and not related to heating/cooling I would personally want to look at these things:
1) solid 5v to the processor(s)
2) correct and stable clocks
3) POR lines
4) SDI and SDO lines (if used) from the processor
5) signs of liquid spills into the keyboard