reset bank indexes when cart is changed

src/studio.c

@@ -1067,10 +1067,17 @@ void showDialog(const char** text, s32 rows, DialogCallback callback, void* data
 	}
 }
 
+static void resetBanks()
+{
+	SDL_memset(studio.bank.indexes, 0, sizeof studio.bank.indexes);
+}
+
 static void initModules()
 {
 	tic_mem* tic = studio.tic;
 
+	resetBanks();
+
 	for(s32 i = 0; i < TIC_EDITOR_BANKS; i++)
 	{
 		initCode(studio.editor[i].code, studio.tic, &tic->cart.banks[i].code);