diff --git a/src/engine/platform/su.cpp b/src/engine/platform/su.cpp
index a28ed304..13650345 100644
--- a/src/engine/platform/su.cpp
+++ b/src/engine/platform/su.cpp
@@ -357,7 +357,7 @@ int DivPlatformSoundUnit::dispatch(DivCommand c) {
       writeControlUpper(c.chan);
       break;
     case DIV_CMD_C64_FINE_CUTOFF:
-      chan[c.chan].baseCutoff=c.value;
+      chan[c.chan].baseCutoff=c.value*4;
       if (!chan[c.chan].std.ex1.has) {
         chan[c.chan].cutoff=chan[c.chan].baseCutoff;
         chWrite(c.chan,0x06,chan[c.chan].cutoff&0xff);
diff --git a/src/engine/sysDef.cpp b/src/engine/sysDef.cpp
index 5ac6bf34..0487873b 100644
--- a/src/engine/sysDef.cpp
+++ b/src/engine/sysDef.cpp
@@ -1447,7 +1447,7 @@ void DivEngine::registerSystems() {
     {0x21, {DIV_CMD_SU_SWEEP_ENABLE, "21xx: Toggle volume sweep (bit 0-4: speed; bit 5: direciton is up; bit 6: loop; bit 7: alternate)", constVal<1>, effectVal}},
     {0x22, {DIV_CMD_SU_SWEEP_ENABLE, "22xx: Toggle cutoff sweep (bit 0-6: speed; bit 7: direction is up)", constVal<2>, effectVal}},
   };
-  const EffectHandler suCutoffHandler(DIV_CMD_C64_FINE_DUTY, "4xxx: Set cutoff (0 to FFF)", effectValLong<12>);
+  const EffectHandler suCutoffHandler(DIV_CMD_C64_FINE_CUTOFF, "4xxx: Set cutoff (0 to FFF)", effectValLong<12>);
   for (int i=0; i<16; i++) {
     suEffectHandlerMap.emplace(0x40+i, suCutoffHandler);
   }