diff --git a/libs/temporal/tempo.cc b/libs/temporal/tempo.cc
index a447646b9d..0d0a3ed887 100644
--- a/libs/temporal/tempo.cc
+++ b/libs/temporal/tempo.cc
@@ -636,6 +636,36 @@ MeterPoint::get_state () const
 	return base;
 }
 
+timepos_t
+TempoMetric::reftime() const
+{
+	TempoMap::SharedPtr tmap (TempoMap::use ());
+	return tmap->reftime (*this);
+}
+
+timepos_t
+TempoMap::reftime (TempoMetric const &tm) const
+{
+	Points::const_iterator pi;
+
+	if (tm.meter().sclock() < tm.tempo().sclock()) {
+		pi = _points.s_iterator_to (*(static_cast<const Point*> (&tm.meter())));
+	} else {
+		pi = _points.s_iterator_to (*(static_cast<const Point*> (&tm.tempo())));
+	}
+
+	/* Walk backwards through points to find a BBT markers, or the start */
+
+	while (pi != _points.begin()) {
+		if (dynamic_cast<const MusicTimePoint*> (&*pi)) {
+			break;
+		}
+		--pi;
+	}
+
+	return timepos_t (pi->sclock());
+}
+
 Temporal::BBT_Argument
 TempoMetric::bbt_at (timepos_t const & pos) const
 {
diff --git a/libs/temporal/temporal/tempo.h b/libs/temporal/temporal/tempo.h
index db132e9089..cf73c8a9ba 100644
--- a/libs/temporal/temporal/tempo.h
+++ b/libs/temporal/temporal/tempo.h
@@ -470,7 +470,7 @@ class LIBTEMPORAL_API TempoMetric
 	TempoMetric (TempoPoint const & t, MeterPoint const & m) : _tempo (&t), _meter (&m) {}
 	virtual ~TempoMetric () {}
 
-	timepos_t reftime() const { return timepos_t (std::min (_tempo->sclock(), _meter->sclock())); }
+	timepos_t reftime() const;
 
 	TempoPoint const & tempo() const { return *_tempo; }
 	MeterPoint const & meter() const { return *_meter; }
@@ -711,6 +711,9 @@ class /*LIBTEMPORAL_API*/ TempoMap : public PBD::StatefulDestructible
 
 	LIBTEMPORAL_API static WritableSharedPtr fetch_writable() { _tempo_map_p = write_copy(); return _tempo_map_p; }
 
+	/* not part of public API */
+	timepos_t reftime(TempoMetric const &) const;
+
 	/* and now on with the rest of the show ... */
 
   public: