diff --git a/Senior/SeniorModel.cpp b/Senior/SeniorModel.cpp
index 9d6a4fe..6a8eb0c 100644
--- a/Senior/SeniorModel.cpp
+++ b/Senior/SeniorModel.cpp
@@ -6,28 +6,44 @@ namespace Ottobit
 {
 void Senior::operator()(tick t)
 {
-  // Only compute skipped_frames when the control changes
+  // Only compute skipped_frames when control changes
   if (inputs.s_rate != previous_rate)
   {
     step_size = (1. - inputs.s_rate) * RATE;
     previous_rate = inputs.s_rate;
   }
 
-  // Only compute bit_factor when the control changes
   if (inputs.bits != previous_bits)
   {
     set_bit_factor();
     previous_bits = inputs.bits;
   }
 
+  if (inputs.depth != previous_depth ||
+     inputs.am_fm != previous_am_fm)
+  {
+
+    if (inputs.am_fm < 1.f)
+      am_amp = (inputs.am_fm * 0.5) + (inputs.depth * 0.5);
+    else
+    {
+      am_amp = 2 - inputs.am_fm;
+      fm_amp = inputs.am_fm - 1;
+    }
+
+    previous_depth = inputs.depth;
+    previous_am_fm = inputs.am_fm;
+  }
+
   // Process the input buffer
   for(int i{0}; i < inputs.audio.channels; i++)
   {
     auto* in = inputs.audio[i];
     auto* out = outputs.audio[i % outputs.audio.channels];
 
-    // Init current_frame for each channel
-    double current_frame{crush(in[i])};
+    // Init current_frame and out_frame for each channel
+    double current_frame{crush(in[0])};
+    double out_frame{current_frame};
 
     for(int j{0}; j < t.frames; j++)
     {
@@ -39,28 +55,25 @@ void Senior::operator()(tick t)
         current_frame = crush(in[j]);
       }
 
-      if (!inputs.depth)
-        out[j] = current_frame;
-      else
+      if (inputs.depth)
       {
         lfo.set(inputs.freq, phases[i], 0);
 
         if (inputs.am_fm < 1.f)
-        {
-          double amp = (inputs.am_fm * 0.5) + (inputs.depth * 0.5);
-          out[j] = current_frame * ((lfo.cos() * amp) + (1 - amp));
-        }
+          out_frame = current_frame * (lfo.cos() * am_amp + (1 - am_amp));
         else
         {
           double amp = lfo.cos() * inputs.depth;
           fms[i].delay(amp * .0025 + 1);
-          double am = current_frame * (amp + (1 - inputs.depth));
+          double am = current_frame * (amp + 1 - inputs.depth);
           double fm = fms[i](current_frame);
-          out[j] = (am * (2 - inputs.am_fm)) + (fm * (inputs.am_fm - 1));
+          out_frame = am * am_amp + fm * fm_amp;
         }
 
         phases[i] = lfo.phase();
       }
+
+      out[j] = out_frame;
     }
   }
 }
diff --git a/Senior/SeniorModel.hpp b/Senior/SeniorModel.hpp
index da2ce62..9baa344 100644
--- a/Senior/SeniorModel.hpp
+++ b/Senior/SeniorModel.hpp
@@ -91,8 +91,13 @@ private:
   int bit_factor, step_size{0};
 
 
-  double previous_bits{BITS},
-      previous_rate{1};
+  double
+      previous_bits{BITS},
+      previous_rate{1},
+      previous_depth{0},
+      previous_am_fm{0},
+      am_amp{0},
+      fm_amp{0};
 
   std::vector<float> phases;
   std::vector<int> skipped_frames;