diff --git a/src/gui/doAction.cpp b/src/gui/doAction.cpp
index f27f0a09d..0d43a2eea 100644
--- a/src/gui/doAction.cpp
+++ b/src/gui/doAction.cpp
@@ -643,6 +643,11 @@ void FurnaceGUI::doAction(int what) {
             e->song.ins[curIns]->fm.op[i].rr=15;
             e->song.ins[curIns]->fm.op[i].tl=127;
             e->song.ins[curIns]->fm.op[i].dt=3;
+
+            e->song.ins[curIns]->esfm.op[i].ct=0;
+            e->song.ins[curIns]->esfm.op[i].dt=0;
+            e->song.ins[curIns]->esfm.op[i].modIn=0;
+            e->song.ins[curIns]->esfm.op[i].outLvl=0;
           }
         }
         wantScrollList=true;
diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index 49e7f476c..e96d1b64e 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -1338,7 +1338,7 @@ void FurnaceGUI::drawFMEnv(unsigned char tl, unsigned char ar, unsigned char dr,
       //addAALine(dl,pos3,posSLineVEnd,colorS); //draw vert. line through sustain level
       addAALine(dl,pos1,pos2,color); //A
       addAALine(dl,pos2,posDecayRate0Pt,color); //Line from A to end of graph
-    } else if (d2r==0.0 || ((instType==DIV_INS_OPL || instType==DIV_INS_SNES) && sus==1.0) || (instType==DIV_INS_OPLL && egt!=0.0)) { //envelope stays at the sustain level forever
+    } else if (d2r==0.0 || ((instType==DIV_INS_OPL || instType==DIV_INS_SNES || instType==DIV_INS_ESFM) && sus==1.0) || (instType==DIV_INS_OPLL && egt!=0.0)) { //envelope stays at the sustain level forever
       dl->AddTriangleFilled(posRStart,posREnd,pos1,colorS); //draw release as shaded triangle behind everything
       addAALine(dl,pos3,posSLineHEnd,colorR); //draw horiz line through sustain level
       addAALine(dl,pos3,posSLineVEnd,colorR); //draw vert. line through sustain level