diff --git a/perl/NGCP/Rtpengine/AutoTest.pm b/perl/NGCP/Rtpengine/AutoTest.pm
index 3bafd2f87..ce3551d63 100644
--- a/perl/NGCP/Rtpengine/AutoTest.pm
+++ b/perl/NGCP/Rtpengine/AutoTest.pm
@@ -19,7 +19,7 @@ our @EXPORT;
 BEGIN {
 	require Exporter;
 	@ISA = qw(Exporter);
-	our @EXPORT = qw(autotest_start new_call offer answer ft tt snd srtp_snd rtp rcv srtp_rcv
+	our @EXPORT = qw(autotest_start new_call offer answer ft tt snd srtp_snd rtp rcv srtp_rcv rcv_no
 		srtp_dec escape rtpm rtpmre reverse_tags new_ft new_tt crlf sdp_split rtpe_req offer_answer
 		autotest_init subscribe_request subscribe_answer publish use_json);
 };
@@ -227,6 +227,13 @@ sub rcv {
 	}
 	return @matches;
 }
+sub rcv_no {
+	my ($sock) = @_;
+	Time::HiRes::sleep(0.1);
+	my $p = '';
+	my $addr = $sock->recv($p, 65535, &MSG_DONTWAIT);
+	ok(! defined $addr, "no packet received");
+}
 sub srtp_rcv {
 	my ($sock, $port, $match, $srtp_ctx) = @_;
 	return rcv($sock, $port, $match, \&srtp_dec, $srtp_ctx);
diff --git a/t/auto-daemon-tests-pubsub.pl b/t/auto-daemon-tests-pubsub.pl
index ea66e8fcc..90ed487d4 100755
--- a/t/auto-daemon-tests-pubsub.pl
+++ b/t/auto-daemon-tests-pubsub.pl
@@ -333,9 +333,17 @@ SDP
 snd($sock_a, $port_b, rtp(0, 4001, 7160, 0x6543, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 4001, 7160, 0x6543, "\x00" x 160));
 rcv($sock_c, $port_c, rtpm(8, 4001, 7160, -1, "\x2a" x 160));
+rcv_no($sock_a);
+rcv_no($sock_d);
 snd($sock_b, $port_a, rtp(0, 2001, 4160, 0x3456, "\x00" x 160));
 rcv($sock_a, $port_b, rtpm(0, 2001, 4160, 0x3456, "\x00" x 160));
 rcv($sock_d, $port_d, rtpm(8, 2001, 4160, -1, "\x2a" x 160));
+rcv_no($sock_b);
+rcv_no($sock_c);
+snd($sock_c, $port_c, rtp(0, 8001, 9160, 0x9876, "\x00" x 160));
+rcv_no($sock_a);
+rcv_no($sock_b);
+rcv_no($sock_c);