diff --git a/gst/isomp4/fourcc.h b/gst/isomp4/fourcc.h
index 7952d8e3a0..89cefa1526 100644
--- a/gst/isomp4/fourcc.h
+++ b/gst/isomp4/fourcc.h
@@ -403,6 +403,10 @@ G_BEGIN_DECLS
 #define FOURCC_tenc     GST_MAKE_FOURCC('t','e','n','c')
 #define FOURCC_cenc     GST_MAKE_FOURCC('c','e','n','c')
 
+/* Audible AAX encrypted audio */
+#define FOURCC_aavd     GST_MAKE_FOURCC('a','a','v','d')
+#define FOURCC_adrm     GST_MAKE_FOURCC('a','d','r','m')
+
 G_END_DECLS
 
 #endif /* __FOURCC_H__ */
diff --git a/gst/isomp4/qtdemux.c b/gst/isomp4/qtdemux.c
index 182d0bc06f..2929cb4a92 100644
--- a/gst/isomp4/qtdemux.c
+++ b/gst/isomp4/qtdemux.c
@@ -7856,6 +7856,7 @@ qtdemux_parse_node (GstQTDemux * qtdemux, GNode * node, const guint8 * buffer,
       case FOURCC_mp4a:
       case FOURCC_alac:
       case FOURCC_fLaC:
+      case FOURCC_aavd:
       {
         guint32 version;
         guint32 offset;
diff --git a/gst/isomp4/qtdemux_types.c b/gst/isomp4/qtdemux_types.c
index 9852429ba5..15ad3e5e8b 100644
--- a/gst/isomp4/qtdemux_types.c
+++ b/gst/isomp4/qtdemux_types.c
@@ -225,6 +225,8 @@ static const QtNodeType qt_node_types[] = {
   {FOURCC_av1m, "AV1 Multi-Frame sample group entry", 0},
   {FOURCC_av1s, "AV1 S-Frame sample group entry", 0},
   {FOURCC_av1M, "AV1 Metadata sample group entry", 0},
+  {FOURCC_aavd, "AAX encrypted audio", 0},
+  {FOURCC_adrm, "AAX DRM key data", 0},
   {0, "unknown", 0,},
 };