diff --git a/game/reconstructed/ammobin.cpp b/game/reconstructed/ammobin.cpp
index 7dbe10e..caa9577 100644
--- a/game/reconstructed/ammobin.cpp
+++ b/game/reconstructed/ammobin.cpp
@@ -94,7 +94,21 @@ Derivation
 	);
 
 Receiver::MessageHandlerSet		AmmoBin::MessageHandlers;
-Simulation::AttributeIndexSet	AmmoBin::AttributeIndex;
+
+// AmmoState -> ammoAlarm (@0x194).  Chained to HeatWatcher so the inherited
+// SimulationState (and any parent attrs) resolve -- the old bare AttributeIndex
+// had no parent, so nothing resolved on an AmmoBin.
+const AmmoBin::IndexEntry
+	AmmoBin::AttributePointers[]=
+{
+	ATTRIBUTE_ENTRY(AmmoBin, AmmoState, ammoAlarm)	// @0x194 (0x54 StateIndicator-compatible feed alarm)
+};
+
+Simulation::AttributeIndexSet	AmmoBin::AttributeIndex(
+	ELEMENTS(AmmoBin::AttributePointers),
+	AmmoBin::AttributePointers,
+	HeatWatcher::GetAttributeIndex()
+);
 
 AmmoBin::SharedData
 	AmmoBin::DefaultData(						// resolved as &DAT_005125bc
diff --git a/game/reconstructed/ammobin.hpp b/game/reconstructed/ammobin.hpp
index de82ff7..06d8846 100644
--- a/game/reconstructed/ammobin.hpp
+++ b/game/reconstructed/ammobin.hpp
@@ -113,6 +113,17 @@
 			StateCount
 		};
 
+		// Attribute Support -- audio binds an AudioStateWatcher to AmmoState; it
+		// resolves to ammoAlarm (@0x194, a 0x54 StateIndicator-compatible alarm) so
+		// the feed/reload/empty audio fires on the AmmoState transition.  The static
+		// AttributeIndex (ammobin.cpp) is now chained to HeatWatcher -- previously it
+		// was a bare, unchained index, so even SimulationState resolved to NULL.
+		enum {
+			AmmoStateAttributeID = HeatWatcher::NextAttributeID,
+			NextAttributeID
+		};
+		static const IndexEntry AttributePointers[];
+
 		typedef void
 			(AmmoBin::*Performance)(Scalar time_slice);