exclusive class misbehaves when multiple exclusive class values are used in a preset

[mrbumpy409]

Summary

I discovered that when more than one exclusive class number is used in a preset, strange behavior ensues. Note that the reproduction steps below are most easily performed with a MIDI keyboard connected to Polyphone.

Steps to Reproduce

1. Download and extract exclusive_class_test2.zip.
2. Load exclusive_class_test2.sf2 into Polyphone.
3. The included preset features electric bass on notes 48–59 (C3–B3) and hi-hat on note 60 (C4, or middle C). The electric bass uses exclusive class 2 and the hi-hat uses exclusive class 1. The electric bass is programmed with a long release, so it should keep ringing after the key is released, only ceasing when another electric bass note is played, due to exclusive class.

Test 1

1. Play a note on the electric bass sound (C3–B3) and release the key. It should continue ringing.
2. Quickly play three hi-hat strikes in succession (C4).

Result: Either the second or third hi-hat strike will terminate the electric bass sample.
Expected result: The electric bass sample (exclusive class 2) should not be cut off by the hi-hat (exclusive class 1).

Test 2

1. Play note C3 (electric bass) and release the key. It should continue ringing.
2. Quickly play two hi-hat strikes (C4) followed by bass note G3.

Result: If you do all of this quickly enough, you will hear both C3 and G3 bass notes ringing together. Note, this test can be done with any two electric bass notes, but C3 and G3 make it easy to hear the bug.
Expected result: Notes C3 and G3 shouldn't be allowed to ring simultaneously since they share the same exclusive class (2).