diff --git a/lib/formats/msg.cpp b/lib/formats/msg.cpp
index 44d1f163d..4568440af 100644
--- a/lib/formats/msg.cpp
+++ b/lib/formats/msg.cpp
@@ -110,6 +110,8 @@ int msg_from_sample(struct msg *msg_in, struct sample *smp, struct vlist *signal
 {
 	msg_in->type     = MSG_TYPE_DATA;
 	msg_in->version  = MSG_VERSION;
+	msg_in->rsvd1	 = 0;
+	msg_in->resv2    = 0;
 	msg_in->length   = (uint16_t) smp->length;
 	msg_in->sequence = (uint32_t) smp->sequence;
 	msg_in->ts.sec  = smp->ts.origin.tv_sec;
diff --git a/lib/hooks/stats.cpp b/lib/hooks/stats.cpp
index b6bf63240..94696e402 100644
--- a/lib/hooks/stats.cpp
+++ b/lib/hooks/stats.cpp
@@ -232,12 +232,16 @@ public:
 
 	virtual void prepare()
 	{
+		assert(state == State::CHECKED);
+
 		stats = std::make_shared<villas::Stats>(buckets, warmup);
 
 		/* Register statistic object to path.
 		*
 		* This allows the path code to update statistics. */
 		node->stats = stats;
+
+		state = State::PREPARED;
 	}
 };
 
diff --git a/lib/web.cpp b/lib/web.cpp
index de2db734f..8b60c1484 100644
--- a/lib/web.cpp
+++ b/lib/web.cpp
@@ -170,7 +170,7 @@ void Web::worker()
 	logger->info("Started worker");
 
 	while (running) {
-		lws_service(context, 100);
+		lws_service(context, 10);
 
 		while (!writables.empty()) {
 			wsi = writables.pop();