diff --git a/libavformat/rmdec.c b/libavformat/rmdec.c
index 10e7c2a3df..8cf98c25b5 100644
--- a/libavformat/rmdec.c
+++ b/libavformat/rmdec.c
@@ -637,6 +637,7 @@ static int rm_assemble_video_frame(AVFormatContext *s, ByteIOContext *pb,
         pkt->size = vst->videobufpos + 8*(vst->cur_slice - vst->slices);
         pkt->pts = AV_NOPTS_VALUE;
         pkt->pos = vst->pktpos;
+        vst->slices = 0;
         return 0;
     }