diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index 32e4e4f473..049d26b069 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -1661,6 +1661,9 @@ ARDOUR_UI::update_format ()
 	case MBWF:
 		s << _("MBWF");
 		break;
+	case FLAC:
+		s << _("FLAC");
+		break;
 	}
 
 	s << " ";
diff --git a/gtk2_ardour/session_option_editor.cc b/gtk2_ardour/session_option_editor.cc
index e2775e641d..0ffb4c14d7 100644
--- a/gtk2_ardour/session_option_editor.cc
+++ b/gtk2_ardour/session_option_editor.cc
@@ -179,18 +179,15 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 
 	add_option (_("Media"), new OptionEditorHeading (_("Audio File Format")));
 
-	ComboOption<SampleFormat>* sf = new ComboOption<SampleFormat> (
+	_sf = new ComboOption<SampleFormat> (
 		"native-file-data-format",
 		_("Sample format"),
 		sigc::mem_fun (*_session_config, &SessionConfiguration::get_native_file_data_format),
 		sigc::mem_fun (*_session_config, &SessionConfiguration::set_native_file_data_format)
 		);
-
-	sf->add (FormatFloat, _("32-bit floating point"));
-	sf->add (FormatInt24, _("24-bit integer"));
-	sf->add (FormatInt16, _("16-bit integer"));
-
-	add_option (_("Media"), sf);
+	add_option (_("Media"), _sf);
+	/* refill available sample-formats, depening on file-format */
+	parameter_changed ("native-file-header-format");
 
 	ComboOption<HeaderFormat>* hf = new ComboOption<HeaderFormat> (
 		"native-file-header-format",
@@ -210,6 +207,7 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 #ifdef HAVE_RF64_RIFF
 	hf->add (RF64_WAV, _("RF64 (WAV compatible)"));
 #endif
+	hf->add (FLAC, _("FLAC"));
 
 	add_option (_("Media"), hf);
 
@@ -410,6 +408,13 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 	set_current_page (_("Timecode"));
 }
 
+SessionOptionEditor::~SessionOptionEditor ()
+{
+	delete _vpu;
+	delete _sf;
+	delete _take_name;
+}
+
 void
 SessionOptionEditor::parameter_changed (std::string const & p)
 {
@@ -429,6 +434,25 @@ SessionOptionEditor::parameter_changed (std::string const & p)
 	else if (p == "track-name-take") {
 		_take_name->set_sensitive(_session_config->get_track_name_take());
 	}
+	else if (p == "native-file-header-format") {
+		bool need_refill = true;
+		_sf->clear ();
+		if (_session_config->get_native_file_header_format() == FLAC) {
+			_sf->add (FormatInt24, _("24-bit integer"));
+			_sf->add (FormatInt16, _("16-bit integer"));
+			if (_session_config->get_native_file_data_format() == FormatFloat) {
+				_session_config->set_native_file_data_format (FormatInt24);
+				need_refill = false;
+			}
+		} else {
+			_sf->add (FormatFloat, _("32-bit floating point"));
+			_sf->add (FormatInt24, _("24-bit integer"));
+			_sf->add (FormatInt16, _("16-bit integer"));
+		}
+		if (need_refill) {
+			parameter_changed ("native-file-data-format");
+		}
+	}
 }
 
 /* the presence of absence of a monitor section is not really a regular session
diff --git a/gtk2_ardour/session_option_editor.h b/gtk2_ardour/session_option_editor.h
index 759f28ff18..bf373c8f33 100644
--- a/gtk2_ardour/session_option_editor.h
+++ b/gtk2_ardour/session_option_editor.h
@@ -31,6 +31,7 @@ class SessionOptionEditor : public OptionEditorWindow
 {
 public:
 	SessionOptionEditor (ARDOUR::Session* s);
+	~SessionOptionEditor ();
 
 private:
 	void parameter_changed (std::string const &);
@@ -41,6 +42,7 @@ private:
 	bool get_use_monitor_section ();
 
 	ComboOption<float>* _vpu;
+	ComboOption<ARDOUR::SampleFormat>* _sf;
 	EntryOption* _take_name;
 
 	void save_defaults ();