--- a/libsidplay/src/xsid/xsid.cpp
+++ b/libsidplay/src/xsid/xsid.cpp
@@ -94,10 +94,15 @@ const int8_t XSID::sampleConvertTable[16
     '\x08', '\x19', '\x2a', '\x3b', '\x4c', '\x5d', '\x6e', '\x7f'
 };
 */
-const int8_t XSID::sampleConvertTable[16] =
+const uint8_t XSID::sampleConvertTable[16] =
 {
+#if 0
     '\x80', '\x94', '\xa9', '\xbc', '\xce', '\xe1', '\xf2', '\x03',
     '\x1b', '\x2a', '\x3b', '\x49', '\x58', '\x66', '\x73', '\x7f'
+#else
+     0x80,   0x94,   0xa9,   0xbc,   0xce,   0xe1,   0xf2,   0x03,
+     0x1b,   0x2a,   0x3b,   0x49,   0x58,   0x66,   0x73,   0x7f
+#endif
 };
 
 const char *XSID::credit =
@@ -141,7 +146,7 @@ void channel::free ()
     silence ();
 }
 
-inline int8_t channel::output ()
+inline uint8_t channel::output ()
 {
     outputs++;
     return sample;
@@ -346,7 +351,7 @@ void channel::galwayInit()
     outputs  = 0;
 
     sampleLimit = 8;
-    sample      = (int8_t) galVolume - 8;
+    sample      = galVolume - 8;
     galwayTonePeriod ();
 
     // Calculate the sample offset
@@ -387,7 +392,7 @@ void channel::galwayClock ()
     // See Galway Example...
     galVolume += volShift;
     galVolume &= 0x0f;
-    sample     = (int8_t) galVolume - 8;
+    sample     = galVolume - 8;
     cycles    += cycleCount;
     m_context.schedule (&galwayEvent, cycleCount, m_phase);
     m_context.schedule (&m_xsid, 0, m_phase);
@@ -515,9 +520,9 @@ void XSID::write (uint_least16_t addr, u
     }
 }
 
-int8_t XSID::sampleOutput (void)
+uint8_t XSID::sampleOutput (void)
 {
-    int8_t sample;
+    uint8_t sample;
     sample  = ch4.output ();
     sample += ch5.output ();
     // Automatically compensated for by C64 code
--- a/libsidplay/src/xsid/xsid.h
+++ b/libsidplay/src/xsid/xsid.h
@@ -166,7 +166,7 @@ private:
     uint_least16_t cycleCount; // Counts to zero and triggers!
     uint_least8_t  volShift;
     uint_least8_t  sampleLimit;
-    int8_t         sample;
+    uint8_t        sample;
 
     // Sample Section
     uint_least8_t  samRepeat;
@@ -201,14 +201,14 @@ private:
 
     // Compress address to not leave so many spaces
     uint_least8_t convertAddr(uint_least8_t addr)
-    { return (((addr) & 0x3) | ((addr) >> 3) & 0x0c); }
+    { return (((addr) & 0x3) | (((addr) >> 3) & 0x0c)); }
 
     void    reset    (void);
     uint8_t read     (uint_least8_t  addr)
     { return reg[convertAddr (addr)]; }
     void    write    (uint_least8_t addr, uint8_t data)
     { reg[convertAddr (addr)] = data; }
-    int8_t  output   (void);
+    uint8_t output   (void);
     bool    isGalway (void)
     { return mode == FM_GALWAY; }
 
@@ -238,7 +238,7 @@ private:
     uint8_t             sidData0x18;
     bool                _sidSamples;
     int8_t              sampleOffset;
-    static const int8_t sampleConvertTable[16];
+    static const uint8_t sampleConvertTable[16];
     bool                wasRunning;
 
 private:
@@ -246,7 +246,7 @@ private:
     void    checkForInit         (channel *ch);
     inline  void setSidData0x18  (void);
     inline  void recallSidData0x18 (void);
-    int8_t  sampleOutput         (void);
+    uint8_t  sampleOutput         (void);
     void    sampleOffsetCalc     (void);
     virtual uint8_t readMemByte  (uint_least16_t addr) = 0;
     virtual void    writeMemByte (uint8_t data) = 0;