diff --git a/src/machine/m_ps2_mca.c b/src/machine/m_ps2_mca.c
index 1a2f4d6c6..d3f881b24 100644
--- a/src/machine/m_ps2_mca.c
+++ b/src/machine/m_ps2_mca.c
@@ -375,7 +375,7 @@ ps55_model_50t_read(uint16_t port)
             return ps2.planar_id >> 8;
         case 0x102:
             return ps2.option[0];
-        case 0x103:
+        case 0x103: {
             uint8_t val = 0xff;
             /*
             I/O 103h - Bit 7-4: Memory Card ID (Connector 1 or 3)
@@ -413,7 +413,7 @@ ps55_model_50t_read(uint16_t port)
             }
             ps2_mca_log(" Read MCA %04X %02X %04X:%04X mem_size = %d, ps2option1 = %2X\n", port, val, cs >> 4, cpu_state.pc, mem_size, ps2.option[1]);
             return val;
-        case 0x104:
+        } case 0x104:
             return ps2.option[2];
         case 0x105:
             return ps2.option[3];
@@ -435,7 +435,7 @@ ps55_model_50v_read(uint16_t port)
             return ps2.planar_id >> 8;
         case 0x102:
             return ps2.option[0];
-        case 0x103:
+        case 0x103: {
             uint8_t val = 0xff;
             /*
             I/O 103h - Bit 7-4: Reserved
@@ -460,7 +460,7 @@ ps55_model_50v_read(uint16_t port)
                     break;
             }
             return val;
-        case 0x104:
+        } case 0x104:
             /* Reading cache ID (bit 3-2) always returns zero */
             return ps2.option[2] & 0xf3;
         case 0x105:
diff --git a/src/sound/resid-fp/SID.cpp b/src/sound/resid-fp/SID.cpp
index 5b5506bc3..4db69af0c 100644
--- a/src/sound/resid-fp/SID.cpp
+++ b/src/sound/resid-fp/SID.cpp
@@ -107,8 +107,10 @@ constexpr unsigned int OSC_DAC_BITS = 12;
  * On my 6581R4AR has 0x3A as the only value giving the same output level as 1.prg
  */
 //@{
+#ifdef USE_RESID_UNUSED
 constexpr unsigned int OFFSET_6581 = 0x380;
 constexpr unsigned int OFFSET_8580 = 0x9c0;
+#endif
 //@}
 
 /**
diff --git a/src/sound/resid-fp/WaveformGenerator.cpp b/src/sound/resid-fp/WaveformGenerator.cpp
index be0738bba..847560f2a 100644
--- a/src/sound/resid-fp/WaveformGenerator.cpp
+++ b/src/sound/resid-fp/WaveformGenerator.cpp
@@ -43,7 +43,9 @@ namespace reSIDfp
 constexpr unsigned int FLOATING_OUTPUT_TTL_6581R3  =   54000;
 constexpr unsigned int FLOATING_OUTPUT_FADE_6581R3 =    1400;
 // ~1s
+#ifdef USE_RESID_UNUSED
 constexpr unsigned int FLOATING_OUTPUT_TTL_6581R4  = 1000000;
+#endif
 // ~1s
 constexpr unsigned int FLOATING_OUTPUT_TTL_8580R5  =  800000;
 constexpr unsigned int FLOATING_OUTPUT_FADE_8580R5 =   50000;
@@ -61,7 +63,9 @@ constexpr unsigned int FLOATING_OUTPUT_FADE_8580R5 =   50000;
 constexpr unsigned int SHIFT_REGISTER_RESET_6581R3 =   50000;
 constexpr unsigned int SHIFT_REGISTER_FADE_6581R3  =   15000;
 // ~2.15s
+#ifdef USE_RESID_UNUSED
 constexpr unsigned int SHIFT_REGISTER_RESET_6581R4 = 2150000;
+#endif
 // ~2.8s
 constexpr unsigned int SHIFT_REGISTER_RESET_8580R5 =  986000;
 constexpr unsigned int SHIFT_REGISTER_FADE_8580R5  =  314300;