diff --git a/libavcodec/ws-snd1.c b/libavcodec/ws-snd1.c
index 0f005807ae..bc9ed00938 100644
--- a/libavcodec/ws-snd1.c
+++ b/libavcodec/ws-snd1.c
@@ -178,4 +178,5 @@ AVCodec ff_ws_snd1_decoder = {
     .init           = ws_snd_decode_init,
     .decode         = ws_snd_decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };