diff --git a/libs/ardour/ardour/tempo.h b/libs/ardour/ardour/tempo.h
index 52c4d04b82..08c2eec4dd 100644
--- a/libs/ardour/ardour/tempo.h
+++ b/libs/ardour/ardour/tempo.h
@@ -394,7 +394,7 @@ class LIBARDOUR_API TempoMap : public PBD::StatefulDestructible
 
 	/* TEMPO- AND METER-SENSITIVE FUNCTIONS
 
-	   bbt_time(), beat_at_frame(), frame_at_beat(), frame_time()
+	   bbt_at_frame(), frame_at_bbt(), beat_at_frame(), frame_at_beat()
 	   and bbt_duration_at()
 	   are all sensitive to tempo and meter, and will give answers
 	   that align with the grid formed by tempo and meter sections.
@@ -445,12 +445,12 @@ class LIBARDOUR_API TempoMap : public PBD::StatefulDestructible
 	framepos_t framepos_minus_beats (framepos_t, Evoral::Beats) const;
 	Evoral::Beats framewalk_to_beats (framepos_t pos, framecnt_t distance) const;
 
-	std::pair<double, framepos_t> predict_tempo_position (TempoSection* section, const Timecode::BBT_Time& bbt);
 	void gui_move_tempo (TempoSection*, const framepos_t& frame);
 	void gui_move_meter (MeterSection*, const framepos_t& frame);
 	bool gui_change_tempo (TempoSection*, const Tempo& bpm);
 	void gui_dilate_tempo (TempoSection* tempo, const framepos_t& frame, const framepos_t& end_frame, const double& pulse);
 
+	std::pair<double, framepos_t> predict_tempo_position (TempoSection* section, const Timecode::BBT_Time& bbt);
 	bool can_solve_bbt (TempoSection* section, const Timecode::BBT_Time& bbt);
 
 	PBD::Signal0<void> MetricPositionChanged;
diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 2b5aac45f7..646a15b6f3 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -1926,6 +1926,7 @@ TempoMap::check_solved (const Metrics& metrics) const
 				continue;
 			}
 			if (prev_t) {
+				/* check ordering */
 				if ((t->frame() <= prev_t->frame()) || (t->pulse() <= prev_t->pulse())) {
 					return false;
 				}
@@ -1936,6 +1937,14 @@ TempoMap::check_solved (const Metrics& metrics) const
 						return false;
 					}
 				}
+
+				/* gradient limit - who knows what it should be?
+				   things are also ok (if a little chaotic) without this
+				*/
+				if (fabs (prev_t->c_func()) > 200.0) {
+					//std::cout << "c : " << prev_t->c_func() << std::endl;
+					return false;
+				}
 			}
 			prev_t = t;
 		}