hey look Arisotura made another stupid branch again

src/SPU.cpp

@@ -269,6 +269,7 @@ void Channel::Start()
         Pos = -3;
 
     NoiseVal = 0x7FFF;
+    PrevSample = 0;
     CurSample = 0;
 
     FIFOReadPos = 0;

src/SPU.h

@@ -73,6 +73,7 @@ public:
     bool KeyOn;
     u32 Timer;
     s32 Pos;
+    s16 PrevSample;
     s16 CurSample;
     u16 NoiseVal;