diff --git a/src/engine/instrument.cpp b/src/engine/instrument.cpp
index 68896a45e..7dbf5b3fd 100644
--- a/src/engine/instrument.cpp
+++ b/src/engine/instrument.cpp
@@ -236,40 +236,40 @@ void DivInstrument::putInsData(SafeWriter* w) {
   for (int i=0; i<4; i++) {
     DivInstrumentSTD::OpMacro& op=std.opMacros[i];
     for (int j=0; j<op.amMacro.len; j++) {
-      w->writeC(op.amMacro.val[j]);
+      w->writeC(op.amMacro.val[j]&0xff);
     }
     for (int j=0; j<op.arMacro.len; j++) {
-      w->writeC(op.arMacro.val[j]);
+      w->writeC(op.arMacro.val[j]&0xff);
     }
     for (int j=0; j<op.drMacro.len; j++) {
-      w->writeC(op.drMacro.val[j]);
+      w->writeC(op.drMacro.val[j]&0xff);
     }
     for (int j=0; j<op.multMacro.len; j++) {
-      w->writeC(op.multMacro.val[j]);
+      w->writeC(op.multMacro.val[j]&0xff);
     }
     for (int j=0; j<op.rrMacro.len; j++) {
-      w->writeC(op.rrMacro.val[j]);
+      w->writeC(op.rrMacro.val[j]&0xff);
     }
     for (int j=0; j<op.slMacro.len; j++) {
-      w->writeC(op.slMacro.val[j]);
+      w->writeC(op.slMacro.val[j]&0xff);
     }
     for (int j=0; j<op.tlMacro.len; j++) {
-      w->writeC(op.tlMacro.val[j]);
+      w->writeC(op.tlMacro.val[j]&0xff);
     }
     for (int j=0; j<op.dt2Macro.len; j++) {
-      w->writeC(op.dt2Macro.val[j]);
+      w->writeC(op.dt2Macro.val[j]&0xff);
     }
     for (int j=0; j<op.rsMacro.len; j++) {
-      w->writeC(op.rsMacro.val[j]);
+      w->writeC(op.rsMacro.val[j]&0xff);
     }
     for (int j=0; j<op.dtMacro.len; j++) {
-      w->writeC(op.dtMacro.val[j]);
+      w->writeC(op.dtMacro.val[j]&0xff);
     }
     for (int j=0; j<op.d2rMacro.len; j++) {
-      w->writeC(op.d2rMacro.val[j]);
+      w->writeC(op.d2rMacro.val[j]&0xff);
     }
     for (int j=0; j<op.ssgMacro.len; j++) {
-      w->writeC(op.ssgMacro.val[j]);
+      w->writeC(op.ssgMacro.val[j]&0xff);
     }
   }
 
@@ -696,20 +696,45 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
       op.ssgMacro.open=reader.readC();
     }
 
+    // FM macro low 8 bits
     for (int i=0; i<4; i++) {
       DivInstrumentSTD::OpMacro& op=std.opMacros[i];
-      reader.read(op.amMacro.val,op.amMacro.len);
-      reader.read(op.arMacro.val,op.arMacro.len);
-      reader.read(op.drMacro.val,op.drMacro.len);
-      reader.read(op.multMacro.val,op.multMacro.len);
-      reader.read(op.rrMacro.val,op.rrMacro.len);
-      reader.read(op.slMacro.val,op.slMacro.len);
-      reader.read(op.tlMacro.val,op.tlMacro.len);
-      reader.read(op.dt2Macro.val,op.dt2Macro.len);
-      reader.read(op.rsMacro.val,op.rsMacro.len);
-      reader.read(op.dtMacro.val,op.dtMacro.len);
-      reader.read(op.d2rMacro.val,op.d2rMacro.len);
-      reader.read(op.ssgMacro.val,op.ssgMacro.len);
+      for (int j=0; j<op.amMacro.len; j++) {
+        op.amMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.arMacro.len; j++) {
+        op.arMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.drMacro.len; j++) {
+        op.drMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.multMacro.len; j++) {
+        op.multMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.rrMacro.len; j++) {
+        op.rrMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.slMacro.len; j++) {
+        op.slMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.tlMacro.len; j++) {
+        op.tlMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.dt2Macro.len; j++) {
+        op.dt2Macro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.rsMacro.len; j++) {
+        op.rsMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.dtMacro.len; j++) {
+        op.dtMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.d2rMacro.len; j++) {
+        op.d2rMacro.val[j]=(unsigned char)reader.readC();
+      }
+      for (int j=0; j<op.ssgMacro.len; j++) {
+        op.ssgMacro.val[j]=(unsigned char)reader.readC();
+      }
     }
   }
 
@@ -921,6 +946,7 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
     ws.param3=reader.readC();
     ws.param4=reader.readC();
   }
+
   return DIV_DATA_SUCCESS;
 }