diff --git a/lib/system/smd/private-lib-system-smd.h b/lib/system/smd/private-lib-system-smd.h
index 8ee8367c9..fdd71d61c 100644
--- a/lib/system/smd/private-lib-system-smd.h
+++ b/lib/system/smd/private-lib-system-smd.h
@@ -30,7 +30,7 @@
 #define LWS_SMD_INFLIGHT_GRACE_SECS	(2)
 #endif
 #if !defined(LWS_SMD_MAX_QUEUE_DEPTH)
-#define LWS_SMD_MAX_QUEUE_DEPTH		(12)
+#define LWS_SMD_MAX_QUEUE_DEPTH		(20)
 #endif
 
 #if defined(LWS_WITH_SECURE_STREAMS)
diff --git a/lib/system/smd/smd.c b/lib/system/smd/smd.c
index bb1da1524..83232e985 100644
--- a/lib/system/smd/smd.c
+++ b/lib/system/smd/smd.c
@@ -131,9 +131,12 @@ lws_smd_msg_send(struct lws_context *ctx, void *pay)
 	lws_smd_msg_t *msg = (lws_smd_msg_t *)(((uint8_t *)pay) -
 				LWS_SMD_SS_RX_HEADER_LEN_EFF - sizeof(*msg));
 
-	if (ctx->smd.owner_messages.count >= LWS_SMD_MAX_QUEUE_DEPTH)
+	if (ctx->smd.owner_messages.count >= LWS_SMD_MAX_QUEUE_DEPTH) {
+		lwsl_warn("%s: rejecting message on queue depth %d\n",
+				__func__, (int)ctx->smd.owner_messages.count);
 		/* reject the message due to max queue depth reached */
 		return 1;
+	}
 
 	if (!ctx->smd.delivering)
 		lws_mutex_lock(ctx->smd.lock_peers); /* +++++++++++++++ peers */
diff --git a/minimal-examples/api-tests/api-test-lws_smd/main.c b/minimal-examples/api-tests/api-test-lws_smd/main.c
index 9f3676ed3..05c4d4710 100644
--- a/minimal-examples/api-tests/api-test-lws_smd/main.c
+++ b/minimal-examples/api-tests/api-test-lws_smd/main.c
@@ -68,6 +68,9 @@ _thread_spam(void *d)
 					       (unsigned int)n)) {
 			lwsl_info("%s: send failed\n", __func__);
 			n--;
+			fail++;
+			interrupted = 1;
+			lws_cancel_service(context);
 		}
 #if defined(WIN32)
 		Sleep(3);