I didn't get a manual.
And the labels on the knobs don't always correspond to the function.
And the interactions between the knobs are unpredictable. Even the slightest touch on certain ones seems to get it all out of shape.
Some prominent knobs seem to have no effect. I got an earsplitting feedback at one point, then silence for a long time. Then one morning all was back to normal ( not sure I want to press the buttons)