Patch Collisions
When bands from different segments are downloaded to the same port, instruments in band can overwrite data from a previously downloaded band.
For example, suppose segment A uses a band that assigns a piano to patch number 1, and segment B uses a band that assigns a banjo to the same patch. The application calls IDirectMusicSegment8::Download first for segment A and then for segment B. Even though the bands might be downloaded to different audiopaths, the instrument data is downloaded to the same synthesizer, so any note on a performance channel mapped to patch number 1 will be played by the banjo.
This potential for patch collisions must be taken into account when the content is authored. Different segments should not use different instruments with the same patch number.