diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
index 529317109..fa54b4325 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
@@ -316,7 +316,7 @@ namespace Opm
             // create output thread if enabled and rank is I/O rank
             // async output is enabled by default if pthread are enabled
 #if HAVE_PTHREAD
-            const bool asyncOutputDefault = true;
+            const bool asyncOutputDefault = false;
 #else
             const bool asyncOutputDefault = false;
 #endif