diff --git a/libs/ardour/parameter_descriptor.cc b/libs/ardour/parameter_descriptor.cc
index ee109d58c1..23f12f1710 100644
--- a/libs/ardour/parameter_descriptor.cc
+++ b/libs/ardour/parameter_descriptor.cc
@@ -47,6 +47,7 @@ ParameterDescriptor::ParameterDescriptor(const Evoral::Parameter& parameter)
 	, integer_step(parameter_is_midi (parameter.type ()))
 	, sr_dependent(false)
 	, enumeration(false)
+	, inline_ctrl(false)
 {
 	ScalePoints sp;