diff --git a/common/jack/types.h b/common/jack/types.h
index 2dccf34f..d3fa233d 100644
--- a/common/jack/types.h
+++ b/common/jack/types.h
@@ -451,6 +451,11 @@ typedef void (*JackInfoShutdownCallback)(jack_status_t code, const char* reason,
 #define JACK_DEFAULT_AUDIO_TYPE "32 bit float mono audio"
 #define JACK_DEFAULT_MIDI_TYPE "8 bit raw midi"
 
+/**
+ * Used to check if the current JACK version provides JackPortIsControlVoltage flag.
+ */
+#define JACK_HAS_PORT_IS_CONTROL_VOLTAGE_FLAG 1
+
 /**
  * For convenience, use this typedef if you want to be able to change
  * between float and double. You may want to typedef sample_t to
@@ -515,6 +520,12 @@ enum JackPortFlags {
      */
     JackPortIsTerminal = 0x10,
 
+    /**
+     * if JackPortIsControlVoltage is set, then the audio port is used
+     * as control voltage audio signal.
+     */
+    JackPortIsControlVoltage = 0x20,
+
 };
 
 /**