Hi there,
I bought my Sinbad Pachislo 2nd hand off ebay about a month ago and I've only just noticed this problem.

You know on the extreme left hand side of the control panel there is a red circular button that allows you to switch playing modes.

Generally, by pressing this button you can switch between winlines paying out or banking credits.
Problem is that when I press this button it doesnt switch modes.
The button is actually working because if I press it when there are credits then it pays out the tokens but it doesnt stay in payout mode if you see what I mean.

Im not aware of any settings that would affect this. Im a bit puzzled really!