diff --git a/sf-stream/include/stream_config.hpp b/sf-stream/include/stream_config.hpp
index 614141c..9b7e693 100644
--- a/sf-stream/include/stream_config.hpp
+++ b/sf-stream/include/stream_config.hpp
@@ -1,7 +1,7 @@
 namespace stream_config
 {
     // N of IO threads to receive data from modules.
-    const int STREAM_ZMQ_IO_THREADS = 2;
+    const int STREAM_ZMQ_IO_THREADS = 1;
     // How long should the RECV queue be.
     const size_t STREAM_RCVHWM = 100;
     // Size of buffer between the receiving and sending part.