diff --git a/libavfilter/avfilter.c b/libavfilter/avfilter.c
index b5b3734944..7ce82f8011 100644
--- a/libavfilter/avfilter.c
+++ b/libavfilter/avfilter.c
@@ -1092,8 +1092,9 @@ static int ff_filter_frame_needs_framing(AVFilterLink *link, AVFrame *frame)
                 return 0;
             }
             av_frame_copy_props(pbuf, frame);
-            pbuf->pts = frame->pts +
-                        av_rescale_q(inpos, samples_tb, link->time_base);
+            pbuf->pts = frame->pts;
+            if (pbuf->pts != AV_NOPTS_VALUE)
+                pbuf->pts += av_rescale_q(inpos, samples_tb, link->time_base);
             pbuf->nb_samples = 0;
         }
         nb_samples = FFMIN(insamples,