diff --git a/dvx/dvxApp.c b/dvx/dvxApp.c
index 0890f5f..64a307d 100644
--- a/dvx/dvxApp.c
+++ b/dvx/dvxApp.c
@@ -2853,8 +2853,8 @@ static void pollKeyboard(AppContextT *ctx) {
         }
 
         // Alt+Space — open/close system menu
-        // Enhanced INT 16h: Alt+Space returns scancode 0x02, ascii 0x20
-        if (scancode == 0x02 && ascii == 0x20) {
+        // Enhanced INT 16h: Alt+Space returns scancode 0x39, ascii 0x20
+        if (scancode == 0x39 && ascii == 0x20) {
             if (ctx->sysMenu.active) {
                 closeSysMenu(ctx);
             } else if (ctx->stack.focusedIdx >= 0) {