diff --git a/daemon/media_socket.c b/daemon/media_socket.c
index afb9bb0fd..7d491b7d9 100644
--- a/daemon/media_socket.c
+++ b/daemon/media_socket.c
@@ -2536,11 +2536,26 @@ static bool media_packet_address_check(struct packet_handler_ctx *phc)
 		phc->mp.stream->detected_endpoints[idx] = phc->mp.fsin;
 
 		// now grab the best matched endpoint
-		for (idx = 0; idx < 4; idx++) {
-			use_endpoint_confirm = &phc->mp.stream->detected_endpoints[idx];
+		unsigned int matched_idx;
+		for (matched_idx = 0; matched_idx < 4; matched_idx++) {
+			use_endpoint_confirm = &phc->mp.stream->detected_endpoints[matched_idx];
 			if (use_endpoint_confirm->address.family)
 				break;
 		}
+
+		// finally, if there has been a better match and if strict-source is set,
+		// drop this packet
+		if (PS_ISSET(phc->mp.stream, STRICT_SOURCE) && matched_idx < idx) {
+			ilog(LOG_INFO | LOG_FLAG_LIMIT, "Drop during learning due to strict-source attribute; "
+					"got %s%s%s, "
+					"best match %s%s%s",
+				FMT_M(endpoint_print_buf(&phc->mp.fsin)),
+				FMT_M(endpoint_print_buf(use_endpoint_confirm)));
+			atomic64_inc_na(&phc->mp.stream->stats_in->errors);
+			atomic64_inc_na(&phc->mp.sfd->local_intf->stats->in.errors);
+			ret = true;
+			goto out;
+		}
 	}
 
 	if (wait_time)
diff --git a/t/auto-daemon-tests-heuristic.pl b/t/auto-daemon-tests-heuristic.pl
index facb612b6..20e3b5156 100755
--- a/t/auto-daemon-tests-heuristic.pl
+++ b/t/auto-daemon-tests-heuristic.pl
@@ -359,19 +359,19 @@ snd($sock_a, $port_b, rtp(0, 1001, 3160, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1001, 3160, 0x1234, "\x00" x 160));
 # callee send from different port
 snd($sock_c, $port_a, rtp(0, 2001, 4160, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2001, 4160, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1002, 3320, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1002, 3320, 0x1234, "\x00" x 160));
 # callee send from different address
 snd($sock_d, $port_a, rtp(0, 2002, 4320, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2002, 4320, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1003, 3480, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1003, 3480, 0x1234, "\x00" x 160));
 # callee send from different everything
 snd($sock_e, $port_a, rtp(0, 2003, 4480, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2003, 4480, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1004, 3640, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1004, 3640, 0x1234, "\x00" x 160));
@@ -384,19 +384,19 @@ snd($sock_a, $port_b, rtp(0, 1005, 3800, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1005, 3800, 0x1234, "\x00" x 160));
 # callee send from different port
 snd($sock_c, $port_a, rtp(0, 2005, 4800, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2005, 4800, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1006, 3960, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1006, 3960, 0x1234, "\x00" x 160));
 # callee send from different address
 snd($sock_d, $port_a, rtp(0, 2006, 4960, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2006, 4960, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1007, 4120, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1007, 4120, 0x1234, "\x00" x 160));
 # callee send from different everything
 snd($sock_e, $port_a, rtp(0, 2007, 5120, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2007, 5120, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1008, 4280, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1008, 4280, 0x1234, "\x00" x 160));
@@ -506,7 +506,7 @@ snd($sock_a, $port_b, rtp(0, 1002, 3320, 0x1234, "\x00" x 160));
 rcv($sock_c, $port_a, rtpm(0, 1002, 3320, 0x1234, "\x00" x 160));
 # callee send from different address
 snd($sock_d, $port_a, rtp(0, 2002, 4320, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2002, 4320, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to almost good candidate (different address ignored)
 snd($sock_a, $port_b, rtp(0, 1003, 3480, 0x1234, "\x00" x 160));
 rcv($sock_c, $port_a, rtpm(0, 1003, 3480, 0x1234, "\x00" x 160));
@@ -519,19 +519,19 @@ rcv($sock_b, $port_a, rtpm(0, 1004, 3640, 0x1234, "\x00" x 160));
 
 # callee send from different everything
 snd($sock_e, $port_a, rtp(0, 2004, 4640, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2004, 4640, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1005, 3800, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1005, 3800, 0x1234, "\x00" x 160));
 # callee send from different port
 snd($sock_c, $port_a, rtp(0, 2005, 4800, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2005, 4800, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1006, 3960, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1006, 3960, 0x1234, "\x00" x 160));
 # callee send from different address
 snd($sock_d, $port_a, rtp(0, 2006, 4960, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2006, 4960, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1007, 4120, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1007, 4120, 0x1234, "\x00" x 160));
@@ -547,7 +547,7 @@ sleep(4);
 
 # callee send from different everything
 snd($sock_e, $port_a, rtp(0, 2008, 5280, 0x1234, "\x00" x 160));
-rcv($sock_a, $port_b, rtpm(0, 2008, 5280, 0x1234, "\x00" x 160)); # first packet that confirms the address still gets through
+rcv_no($sock_a);
 # caller send, forward to expected
 snd($sock_a, $port_b, rtp(0, 1009, 4440, 0x1234, "\x00" x 160));
 rcv($sock_b, $port_a, rtpm(0, 1009, 4440, 0x1234, "\x00" x 160));