diff --git a/index.js b/index.js
index 56e17f1e..4fd1afc0 100644
--- a/index.js
+++ b/index.js
@@ -927,7 +927,7 @@ const fileType = input => {
 		};
 	}
 
-	if (check([0x77, 0x0B])) {
+	if (check([0x0B, 0x77])) {
 		return {
 			ext: 'ac3',
 			mime: 'audio/vnd.dolby.dd-raw'
diff --git a/test.js b/test.js
index 7f073eda..53df6f11 100644
--- a/test.js
+++ b/test.js
@@ -105,7 +105,8 @@ const types = [
 	'glb',
 	'pcap',
 	'dsf',
-	'voc'
+	'voc',
+	'ac3'
 ];
 
 // Define an entry here only if the fixture has a different