It is fantastic how one's brain works. At 6 am on Saturday morning I managed, without any problems at all, find Fish Fabrique (bar) again. Fish Fabrique is located a bit off the beaten path, inside a dark alleyway, through a metal fire door. Downstairs. Through another metal fire door...then you can follow the music. Easy!
It is also amazing that I was still up at 6 am, on my way to another bar!