I don't know if it's our bug, or a bug in the original Kyra music driver, but

updateCallback3() would call unkOutput2(9) in at least one case. This is
obviously wrong because it a) reads outside _regOffsets[], and b) writes to
invalid Adlib registers.

Now unkOutput2() has the same safeguards as noteOff() already had, making
callbackOutput() and updateCallback3() even more similar.

svn-id: r21335

1 files changed, 6 insertions, 3 deletions

diff --git a/engines/kyra/sound_adlib.cpp b/engines/kyra/sound_adlib.cpp
index 68c481f235..52113bdcd0 100644
--- a/engines/kyra/sound_adlib.cpp
+++ b/engines/kyra/sound_adlib.cpp
@@ -612,9 +612,7 @@ void AdlibDriver::callbackOutput() {
 			channel.tempo = 0xFF;
 			channel.position = 0xFF;
 			channel.duration = 1;
-			if (chan != 9) {
-				unkOutput2(chan);
-			}
+			unkOutput2(chan);
 		}
 
 		++_lastProcessed;
@@ -786,6 +784,11 @@ void AdlibDriver::noteOff(Channel &channel) {
 void AdlibDriver::unkOutput2(uint8 chan) {
 	debugC(9, kDebugLevelSound, "unkOutput2(%d)", chan);
 
+	// The control channel has no corresponding Adlib channel
+
+	if (chan >= 9)
+		return;
+
 	// I believe this has to do with channels 6, 7, and 8 being special
 	// when Adlib's rhythm section is enabled.