diff --git a/README.md b/README.md
index e54d0e24..174f9e92 100644
--- a/README.md
+++ b/README.md
@@ -66,7 +66,7 @@ $config->setMetadataRefreshIntervalMs(10000);
 $config->setMetadataBrokerList('10.13.4.159:9192');
 $config->setBrokerVersion('1.0.0');
 $config->setRequiredAck(1);
-$config->setIsAsyn(false);
+$config->setIsAsyn(true);
 $config->setProduceInterval(500);
 $producer = new \Kafka\Producer(
     function() {
diff --git a/README_CH.md b/README_CH.md
index 4fbd3a70..9c0eb6c4 100644
--- a/README_CH.md
+++ b/README_CH.md
@@ -60,7 +60,7 @@ $config->setMetadataRefreshIntervalMs(10000);
 $config->setMetadataBrokerList('10.13.4.159:9192');
 $config->setBrokerVersion('0.9.0.1');
 $config->setRequiredAck(1);
-$config->setIsAsyn(false);
+$config->setIsAsyn(true);
 $config->setProduceInterval(500);
 $producer = new \Kafka\Producer(function() {
 	return array(
diff --git a/example/Producer.php b/example/Producer.php
index 13ffd22d..222b2001 100644
--- a/example/Producer.php
+++ b/example/Producer.php
@@ -20,7 +20,7 @@
 $config->setMetadataBrokerList('127.0.0.1:9093');
 $config->setBrokerVersion('1.0.0');
 $config->setRequiredAck(1);
-$config->setIsAsyn(false);
+$config->setIsAsyn(true);
 $config->setProduceInterval(500);
 $config->setSecurityProtocol(Config::SECURITY_PROTOCOL_SASL_SSL);
 $config->setSaslMechanism(Config::SASL_MECHANISMS_SCRAM_SHA_256);