diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 8993a7d76..689e26385 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -916,7 +916,9 @@ void FurnaceGUI::noteInput(int num, int key, int vol) {
     pat->data[cursor.y][1]=(unsigned char)pat->data[cursor.y][1];
     if (latchIns==-2) {
       if (curIns>=(int)e->song.ins.size()) curIns=-1;
-      pat->data[cursor.y][2]=curIns;
+      if (curIns>=0) {
+        pat->data[cursor.y][2]=curIns;
+      }
     } else if (latchIns!=-1 && !e->song.ins.empty()) {
       pat->data[cursor.y][2]=MIN(((int)e->song.ins.size())-1,latchIns);
     }