diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index e5073089d9..438c43f613 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -1515,8 +1515,8 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size,
                 continue;
 
 again:
-            if (   !(avctx->active_thread_type & FF_THREAD_FRAME)
-                || nals_needed >= nal_index)
+            if (   (!(avctx->active_thread_type & FF_THREAD_FRAME) || nals_needed >= nal_index)
+                && !h->current_slice)
                 h->au_pps_id = -1;
             /* Ignore per frame NAL unit type during extradata
              * parsing. Decoding slices is not possible in codec init