diff --git a/libs/ardour/ardour/midi_region.h b/libs/ardour/ardour/midi_region.h
index 75a03c7887..1957d34680 100644
--- a/libs/ardour/ardour/midi_region.h
+++ b/libs/ardour/ardour/midi_region.h
@@ -156,10 +156,10 @@ class LIBARDOUR_API MidiRegion : public Region
 
 	bool set_name (const std::string & str);
 
-	void set_position_internal (timepos_t pos);
+	void set_position_internal (timepos_t const & pos);
 	void set_length_internal (timecnt_t const & len);
 	void set_start_internal (timecnt_t const &);
-	void trim_to_internal (timepos_t position, timecnt_t const & length);
+	void trim_to_internal (timepos_t const & position, timecnt_t const & length);
 	void update_length_beats ();
 
 	void model_changed ();
diff --git a/libs/ardour/midi_region.cc b/libs/ardour/midi_region.cc
index c48604112a..debbf8f68b 100644
--- a/libs/ardour/midi_region.cc
+++ b/libs/ardour/midi_region.cc
@@ -327,7 +327,7 @@ MidiRegion::update_length_beats (const int32_t sub_num)
 }
 
 void
-MidiRegion::set_position_internal (samplepos_t pos, bool allow_bbt_recompute, const int32_t sub_num)
+MidiRegion::set_position_internal (timepos_t const & pos, bool allow_bbt_recompute, const int32_t sub_num)
 {
 	Region::set_position_internal (pos, allow_bbt_recompute, sub_num);
 
@@ -737,7 +737,7 @@ MidiRegion::set_start_internal (samplecnt_t s, const int32_t sub_num)
 }
 
 void
-MidiRegion::trim_to_internal (samplepos_t position, samplecnt_t length, const int32_t sub_num)
+MidiRegion::trim_to_internal (timepos_t const &  position, samplecnt_t length, const int32_t sub_num)
 {
 	if (locked()) {
 		return;