diff --git a/src/boards/116.c b/src/boards/116.c
index 88f5f00..cb7d40f 100644
--- a/src/boards/116.c
+++ b/src/boards/116.c
@@ -250,10 +250,10 @@ static DECLFW(UNLSL12Write) {
 				mmc1_regs[n] = mmc1_buffer;
 				mmc1_buffer = mmc1_shift = 0;
 				switch (n) {
-				case 0: SyncMIR();
-				case 2: SyncCHR();
+				case 0: SyncMIR(); break;
+				case 2: SyncCHR(); break;
 				case 3:
-				case 1: SyncPRG();
+				case 1: SyncPRG(); break;
 				}
 			}
 		}
diff --git a/src/boards/bmc13in1jy110.c b/src/boards/bmc13in1jy110.c
index c7bd349..0f70257 100644
--- a/src/boards/bmc13in1jy110.c
+++ b/src/boards/bmc13in1jy110.c
@@ -41,11 +41,13 @@ static void Sync(void) {
 	case 1:
 		setprg16(0x8000, ((8 + (bank_value & 7)) >> 1) + prgb[1]);
 		setprg16(0xC000, (bank_value & 7) >> 1);
+		break;
 	case 4:
 		setprg32(0x8000, 8 + (bank_value & 7)); break;
 	case 5:
 		setprg16(0x8000, ((8 + (bank_value & 7)) >> 1) + prgb[1]);
 		setprg16(0xC000, ((8 + (bank_value & 7)) >> 1) + prgb[3]);
+		break;
 	case 2:
 		setprg8(0x8000, prgb[0] >> 2);
 		setprg8(0xa000, prgb[1]);
diff --git a/src/boards/yoko.c b/src/boards/yoko.c
index e91974a..f27ab6f 100644
--- a/src/boards/yoko.c
+++ b/src/boards/yoko.c
@@ -117,7 +117,7 @@ static DECLFW(UNLYOKOWrite) {
 
 static DECLFW(M83Write) {
 	switch (A) {
-	case 0x8000: is2kbank = 1;
+	case 0x8000: is2kbank = 1; M83Sync(); break;
 	case 0xB000:												/* Dragon Ball Z Party [p1] BMC */
 	case 0xB0FF:												/* Dragon Ball Z Party [p1] BMC */
 	case 0xB1FF: bank = V; mode |= 0x40; M83Sync(); break;		/* Dragon Ball Z Party [p1] BMC */
diff --git a/src/fds.c b/src/fds.c
index 3501915..302fdae 100644
--- a/src/fds.c
+++ b/src/fds.c
@@ -346,6 +346,7 @@ static DECLFW(FDSWrite) {
 			X6502_IRQEnd(FCEU_IQEXT);
 			X6502_IRQEnd(FCEU_IQEXT2);
 		}
+		break;
 	case 0x4024:
 #ifndef USE_DINK
 		if ((InDisk != 255) && !(FDSRegs[5] & 0x4) && (FDSRegs[3] & 0x1)) {