diff --git a/video/decode/vd_lavc.c b/video/decode/vd_lavc.c
index 0367c2afed..2f47659bde 100644
--- a/video/decode/vd_lavc.c
+++ b/video/decode/vd_lavc.c
@@ -410,6 +410,7 @@ static void uninit_avctx(sh_video_t *sh)
 #if !HAVE_AVUTIL_REFCOUNTING
     mp_buffer_pool_free(&ctx->dr1_buffer_pool);
 #endif
+    ctx->last_sample_aspect_ratio = (AVRational){0, 0};
 }
 
 static void uninit(sh_video_t *sh)