Extracted staffVolumeDown to seperate file

src/main.cpp

@@ -55,26 +55,7 @@ void loop()
   // SW2 - Staff Volume Down
   if (!debounceRead(BTN_STAFF_DWN))
   {
-    if (maxVolume > STAFF_STEPS)
-    {
-      maxVolume -= STAFF_STEPS;
-
-      if (userVolume > maxVolume)
-      {
-        for (int i = 0; i < (userVolume - maxVolume); i++)
-        {
-          potDecrement();
-        }
-
-        userVolume = maxVolume;
-        oldUserVolume = userVolume;
-      }
-
-      if (oldUserVolume > maxVolume)
-      {
-        oldUserVolume = maxVolume;
-      }
-    }
+    staffVolumeDown(maxVolume, &userVolume, &oldUserVolume);
   }
 
   // Remote D - Mute

src/staffFunctions.cpp

@@ -1,5 +1,6 @@
 #include <staffFunctions.h>
 #include <constants.h>
+#include <potControlls.h>
 
 void staffVolumeUp(int *maxVolume)
 {
@@ -7,4 +8,28 @@ void staffVolumeUp(int *maxVolume)
     {
         *maxVolume += STAFF_STEPS;
     }
+}
+
+void staffVolumeDown(int maxVolume, int *userVolume, int *oldUserVolume)
+{
+    if (maxVolume > STAFF_STEPS)
+    {
+        maxVolume -= STAFF_STEPS;
+
+        if (*userVolume > maxVolume)
+        {
+            for (int i = 0; i < (*userVolume - maxVolume); i++)
+            {
+                potDecrement();
+            }
+
+            *userVolume = maxVolume;
+            *oldUserVolume = *userVolume;
+        }
+
+        if (*oldUserVolume > maxVolume)
+        {
+            *oldUserVolume = maxVolume;
+        }
+    }
 }