Basically exactly as in the title - I want to map wave files to a midi
sequence. I think some way of using Soundbank and SoundbankResource is
required, but I haven't been able to make much sense of the documentation.

From SoundbankResource documentation:
"Audio samples. A sample typically is a sampled audio waveform which
contains a short sound recording whose duration is a fraction of a
second, or at most a few seconds. These audio samples may be used by a
Synthesizer to synthesize sound in response to MIDI commands"

So I think I'm going to need to create my own custom synthesizer
rather than use the system one.

Can someone help me out? Perhaps give me a rough idea (pseudocode) of
how to code this?