diff --git a/src/sfizz/Region.cpp b/src/sfizz/Region.cpp
index d0f2e706..94d0218e 100644
--- a/src/sfizz/Region.cpp
+++ b/src/sfizz/Region.cpp
@@ -733,17 +733,17 @@ bool sfz::Region::parseOpcode(const Opcode& opcode)
         setCCPairFromOpcode(opcode, amplitudeEG.ccSustain, Default::egOnCCPercentRange);
         break;
 
-    case hash("effect"): // effect&
+    case hash("effect&"):
     {
-        const auto effectNumber = opcode.backParameter();
-        if (!effectNumber || *effectNumber < 1 || *effectNumber > config::maxEffectBuses)
+        const auto effectNumber = opcode.parameters.back();
+        if (!effectNumber || effectNumber < 1 || effectNumber > config::maxEffectBuses)
             break;
         auto value = readOpcode<float>(opcode.value, { 0, 100 });
         if (!value)
             break;
-        if (static_cast<size_t>(*effectNumber + 1) > gainToEffect.size())
-            gainToEffect.resize(*effectNumber + 1);
-        gainToEffect[*effectNumber] = *value / 100;
+        if (static_cast<size_t>(effectNumber + 1) > gainToEffect.size())
+            gainToEffect.resize(effectNumber + 1);
+        gainToEffect[effectNumber] = *value / 100;
         break;
     }
 
diff --git a/src/sfizz/Synth.cpp b/src/sfizz/Synth.cpp
index efefd1e7..67dadef1 100644
--- a/src/sfizz/Synth.cpp
+++ b/src/sfizz/Synth.cpp
@@ -223,24 +223,18 @@ void sfz::Synth::handleEffectOpcodes(const std::vector<Opcode>& members)
                 getOrCreateBus(0).setGainToMain(*valueOpt / 100);
             break;
 
-        case hash("fxtomain"): // fx&tomain
-            if (auto numberOpt = opcode.firstParameter()) {
-                unsigned number = *numberOpt;
-                if (number < 1 || number > config::maxEffectBuses)
-                    break;
-                if (auto valueOpt = readOpcode<float>(opcode.value, { 0, 100 }))
-                    getOrCreateBus(number).setGainToMain(*valueOpt / 100);
-            }
+        case hash("fx&tomain"): // fx&tomain
+            if (opcode.parameters.front() < 1 || opcode.parameters.front() > config::maxEffectBuses)
+                break;
+            if (auto valueOpt = readOpcode<float>(opcode.value, { 0, 100 }))
+                getOrCreateBus(opcode.parameters.front()).setGainToMain(*valueOpt / 100);
             break;
 
-        case hash("fxtomix"): // fx&tomix
-            if (auto numberOpt = opcode.firstParameter()) {
-                unsigned number = *numberOpt;
-                if (number < 1 || number > config::maxEffectBuses)
-                    break;
-                if (auto valueOpt = readOpcode<float>(opcode.value, { 0, 100 }))
-                    getOrCreateBus(number).setGainToMix(*valueOpt / 100);
-            }
+        case hash("fx&tomix"): // fx&tomix
+            if (opcode.parameters.front() < 1 || opcode.parameters.front() > config::maxEffectBuses)
+                break;
+            if (auto valueOpt = readOpcode<float>(opcode.value, { 0, 100 }))
+                getOrCreateBus(opcode.parameters.front()).setGainToMix(*valueOpt / 100);
             break;
         }
     }