diff --git a/mods/d2k/rules/infantry.yaml b/mods/d2k/rules/infantry.yaml
index 07e68141f5..4ecee1381c 100644
--- a/mods/d2k/rules/infantry.yaml
+++ b/mods/d2k/rules/infantry.yaml
@@ -109,6 +109,11 @@ thumper:
 		Sequence: thump-sand
 		UpgradeTypes: deployed
 		UpgradeMinEnabledLevel: 1
+	AmbientSound:
+		SoundFile: THUMPER1.WAV
+		Interval: 60
+		UpgradeTypes: deployed
+		UpgradeMinEnabledLevel: 1
 	AttractsWorms:
 		Intensity: 1000
 		UpgradeTypes: deployed