diff --git a/src/config_passthrough.cpp b/src/config_passthrough.cpp
index 74dfc15c..de5f449b 100644
--- a/src/config_passthrough.cpp
+++ b/src/config_passthrough.cpp
@@ -31,7 +31,7 @@ template<>
 int
 Passthrough::from_string(const std::string &s_)
 {
-  _data = (int)BE_Passthrough::_from_string(s_);
+  _data = (int)BE_Passthrough::_from_string(s_.c_str());
   if(s_ == "off")
     _data = Passthrough::ENUM::OFF;
   ef(s_ == "ro")