diff --git a/gtk2_ardour/pianoroll.cc b/gtk2_ardour/pianoroll.cc
index 6f3fa256cb1..304403180fe 100644
--- a/gtk2_ardour/pianoroll.cc
+++ b/gtk2_ardour/pianoroll.cc
@@ -683,6 +683,11 @@ Pianoroll::snap_to_internal (timepos_t& start, Temporal::RoundMode direction, Sn
 void
 Pianoroll::set_samples_per_pixel (samplecnt_t spp)
 {
+
+	if (spp < 1) {
+		return;
+	}
+
 	EC_LOCAL_TEMPO_SCOPE;
 
 	CueEditor::set_samples_per_pixel (spp);