2 files changed, 6 insertions, 2 deletions
diff --git a/gr-digital/include/gnuradio/digital/header_payload_demux.h b/gr-digital/include/gnuradio/digital/header_payload_demux.h
index 4fd3f8c2f2..d68c4ab9f3 100644
--- a/gr-digital/include/gnuradio/digital/header_payload_demux.h
+++ b/gr-digital/include/gnuradio/digital/header_payload_demux.h
@@ -58,6 +58,9 @@ namespace gr {
      * should go on the payload.
      * A special case are tags on items that make up the guard interval. These are copied
      * to the first item of the following symbol.
+     * If a tag is situated very close to the end of the payload, it might be unclear if
+     * it belongs to this packet or the following. In this case, the tag might be propagated
+     * twice.
      *
      * Tags outside of packets are generally discarded. If this information is important,
      * there are two additional mechanisms to preserve the tags:
diff --git a/gr-digital/lib/header_payload_demux_impl.cc b/gr-digital/lib/header_payload_demux_impl.cc
index 406d59e246..15308c0be1 100644
--- a/gr-digital/lib/header_payload_demux_impl.cc
+++ b/gr-digital/lib/header_payload_demux_impl.cc
@@ -266,10 +266,11 @@ namespace gr {
 
 	case STATE_PAYLOAD:
 	  if (check_items_available(d_curr_payload_len, ninput_items, noutput_items, nread)) {
-	    update_special_tags(0, d_curr_payload_len * (d_items_per_symbol + d_gi));
+	    // The -1 because we won't consume the last item, it might hold the next trigger.
+	    update_special_tags(0, (d_curr_payload_len - 1) * (d_items_per_symbol + d_gi));
 	    copy_n_symbols(in, out_payload, PORT_PAYLOAD, d_curr_payload_len);
 	    produce(PORT_PAYLOAD, d_curr_payload_len * (d_output_symbols ? 1 : d_items_per_symbol));
-	    consume_each (d_curr_payload_len * (d_items_per_symbol + d_gi));
+	    consume_each ((d_curr_payload_len - 1) * (d_items_per_symbol + d_gi)); // Same here
 	    set_min_noutput_items(d_output_symbols ? 1 : (d_items_per_symbol + d_gi));
 	    d_state = STATE_FIND_TRIGGER;
 	  }