diff --git a/daemon/browser.cpp b/daemon/browser.cpp
index d5835c9..c6c1ed9 100644
--- a/daemon/browser.cpp
+++ b/daemon/browser.cpp
@@ -100,7 +100,9 @@ bool Browser::worker() {
           uint32_t last_seen =
               duration_cast<second_t>(steady_clock::now() - startup_).count();
           auto upd_source{*it};
-          upd_source.announce_period = last_seen - upd_source.last_seen;
+          if ((last_seen - upd_source.last_seen) != 0) {
+              upd_source.announce_period = last_seen - upd_source.last_seen;
+          }
           upd_source.last_seen = last_seen;
           sources_.replace(it, upd_source);
         } else {