diff --git a/inc/lib/webm/ffmpeg.php b/inc/lib/webm/ffmpeg.php
index b4750862..6974b4a8 100644
--- a/inc/lib/webm/ffmpeg.php
+++ b/inc/lib/webm/ffmpeg.php
@@ -123,7 +123,7 @@ function is_valid_webm(array $ffprobe_out) {
 		$any_aac = false;
 		if ($audio_idx !== null) {
 			for ($i = 0; $i < count($trackmap['audioat']); $i++) {
-				if ($ffprobe_out['streams'][$i]['codec_name'] == 'h264') {
+				if ($ffprobe_out['streams'][$i]['codec_name'] == 'acc') {
 					$audio_idx = $i;
 					$any_aac = true;
 					break;