"Relearning" parameters
This can be thought of as an active learning problem. You want feedback from the learning process to influence what kind of input examples you next train on.  Active learning is still a difficult problem in most settings. 

As @cohoz points out, hill climbing is an intuitive option in this case, but only if you always want to increase or decrease your measure of frustration. If instead the goal is to explore frustration as a function of as much of the music parameter feature space as possible, you will want to read about active learning and uncertainty.