diff --git a/libs/surfaces/generic_midi/generic_midi_control_protocol.cc b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
index 44b9351554..3c0507abec 100644
--- a/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
+++ b/libs/surfaces/generic_midi/generic_midi_control_protocol.cc
@@ -1232,11 +1232,11 @@ GenericMidiControlProtocol::create_function (const XMLNode& node)
 		ev = MIDI::program;
 	} else if ((prop = node.property (X_("sysex"))) != 0 || (prop = node.property (X_("msg"))) != 0) {
 
-                if (prop->name() == X_("sysex")) {
-                        ev = MIDI::sysex;
-                } else {
-                        ev = MIDI::any;
-                }
+		if (prop->name() == X_("sysex")) {
+			ev = MIDI::sysex;
+		} else {
+			ev = MIDI::any;
+		}
 
 		int val;
 		uint32_t cnt;
@@ -1332,11 +1332,11 @@ GenericMidiControlProtocol::create_action (const XMLNode& node)
 		ev = MIDI::program;
 	} else if ((prop = node.property (X_("sysex"))) != 0 || (prop = node.property (X_("msg"))) != 0) {
 
-                if (prop->name() == X_("sysex")) {
-                        ev = MIDI::sysex;
-                } else {
-                        ev = MIDI::any;
-                }
+		if (prop->name() == X_("sysex")) {
+			ev = MIDI::sysex;
+		} else {
+			ev = MIDI::any;
+		}
 
 		int val;
 		uint32_t cnt;
diff --git a/libs/surfaces/generic_midi/generic_midi_control_protocol.h b/libs/surfaces/generic_midi/generic_midi_control_protocol.h
index c198969ca0..bd7e646282 100644
--- a/libs/surfaces/generic_midi/generic_midi_control_protocol.h
+++ b/libs/surfaces/generic_midi/generic_midi_control_protocol.h
@@ -39,7 +39,7 @@ namespace ARDOUR {
 }
 
 namespace MIDI {
-    class Port;
+	class Port;
 }
 
 class MIDIControllable;
@@ -144,8 +144,8 @@ private:
 	};
 	typedef std::list<MIDIPendingControllable* > MIDIPendingControllables;
 	MIDIPendingControllables pending_controllables;
-        Glib::Threads::Mutex controllables_lock;
-        Glib::Threads::Mutex pending_lock;
+	Glib::Threads::Mutex controllables_lock;
+	Glib::Threads::Mutex pending_lock;
 
 	bool start_learning (boost::weak_ptr<PBD::Controllable>);
 	void stop_learning (boost::weak_ptr<PBD::Controllable>);
diff --git a/libs/surfaces/generic_midi/midicontrollable.cc b/libs/surfaces/generic_midi/midicontrollable.cc
index 741cd0c781..ee08bd70a9 100644
--- a/libs/surfaces/generic_midi/midicontrollable.cc
+++ b/libs/surfaces/generic_midi/midicontrollable.cc
@@ -725,7 +725,7 @@ MIDIControllable::write_feedback (MIDI::byte* buf, int32_t& bufsize, bool /*forc
 		return buf;
 	}
 
-        DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("Feedback: %1 %2\n", control_description(), current_uri()));
+	DEBUG_TRACE (DEBUG::GenericMidi, string_compose ("Feedback: %1 %2\n", control_description(), current_uri()));
 
 	*buf++ = (0xF0 & control_type) | (0xF & control_channel);
 	int ev_size = 3;