diff --git a/Source/MIKMIDISynthesizerInstrument.m b/Source/MIKMIDISynthesizerInstrument.m
index b400ad39..4244380b 100644
--- a/Source/MIKMIDISynthesizerInstrument.m
+++ b/Source/MIKMIDISynthesizerInstrument.m
@@ -34,7 +34,7 @@ - (BOOL)isEqual:(id)object
 {
 	if (object == self) return YES;
 	if (![object isMemberOfClass:[self class]]) return NO;
-	if (!self.instrumentID == [object instrumentID]) return NO;
+	if (self.instrumentID != [object instrumentID]) return NO;
 	return [self.name isEqualToString:[object name]];
 }