Alright, let's take these one at a time. The first message is "243 186 2", which translates to 0xF3 186 (Song Select #186), and I don't know about the leftover 2. So right away there is some mystery.
I would expect a note-on event, as in this table:
which would be 0x9N NoteNumber Velocity, where N is the channel number. All of your data is entirely strange. How about you just play one note (middle C) and let's study that by itself.
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