diff --git a/src/engine/platform/genesisshared.h b/src/engine/platform/genesisshared.h
index 01d45f955..6410ddb27 100644
--- a/src/engine/platform/genesisshared.h
+++ b/src/engine/platform/genesisshared.h
@@ -44,6 +44,6 @@ static int orderedOps[4]={
 
 #define rWrite(a,v) if (!skipRegisterWrites) {pendingWrites[a]=v;}
 #define immWrite(a,v) if (!skipRegisterWrites) {writes.push_back(QueuedWrite(a,v)); if (dumpWrites) {addWrite(a,v);} }
-#define urgentWrite(a,v) if (!skipRegisterWrites) {if (writes.front().addrOrVal) {writes.push_back(QueuedWrite(a,v));} else {writes.push_front(QueuedWrite(a,v));}; if (dumpWrites) {addWrite(a,v);} }
+#define urgentWrite(a,v) if (!skipRegisterWrites) {if (writes.empty() || writes.front().addrOrVal) {writes.push_back(QueuedWrite(a,v));} else {writes.push_front(QueuedWrite(a,v));}; if (dumpWrites) {addWrite(a,v);} }
 
 #include "fmshared_OPN.h"