diff --git a/src/sys/ags_text.cpp b/src/sys/ags_text.cpp
index 1761ca6..2b88d99 100644
--- a/src/sys/ags_text.cpp
+++ b/src/sys/ags_text.cpp
@@ -21,7 +21,7 @@ inline uint16 sjis_to_unicode(uint16 code)
 void AGS::draw_text(char string[])
 {
 	int p = 0;
-	int screen, *dest_x, dest_y, font_size;
+	int screen, dest_x, dest_y, font_size;
 	uint8 font_color;
 
 	uint8 antialias_cache[256*7];
@@ -30,13 +30,13 @@ void AGS::draw_text(char string[])
 
 	if (draw_menu) {
 		screen = 2;
-		dest_x = &menu_dest_x;
+		dest_x = menu_dest_x;
 		dest_y = menu_dest_y;
 		font_size = menu_font_size;
 		font_color = menu_font_color;
 	} else {
 		screen = dest_screen;
-		dest_x = &text_dest_x;
+		dest_x = text_dest_x;
 		dest_y = text_dest_y;
 		font_size = text_font_size;
 		font_color = text_font_color;
@@ -58,19 +58,23 @@ void AGS::draw_text(char string[])
 
 		// 文字出力
 		if((0xeb9f <= code && code <= 0xebfc) || (0xec40 <= code && code <= 0xec9e)) {
-			draw_gaiji(screen, *dest_x, dest_y, code, font_size, font_color);
+			draw_gaiji(screen, dest_x, dest_y, code, font_size, font_color);
 		} else {
 			if (antialias)
-				draw_char_antialias(screen, *dest_x, dest_y, code, font_size, font_color, antialias_cache);
+				draw_char_antialias(screen, dest_x, dest_y, code, font_size, font_color, antialias_cache);
 			else
-				draw_char(screen, *dest_x, dest_y, code, font_size, font_color);
-		}
-		// 画面更新
-		if(screen == 0) {
-			draw_screen(*dest_x, dest_y, (code & 0xff00) ? font_size : (font_size >> 1), font_size);
+				draw_char(screen, dest_x, dest_y, code, font_size, font_color);
 		}
 		// 出力位置の更新
-		*dest_x += (code & 0xff00) ? font_size : (font_size >> 1);
+		dest_x += (code & 0xff00) ? font_size : (font_size >> 1);
+	}
+	if (draw_menu)
+		menu_dest_x = dest_x;
+	else {
+		// 画面更新
+		if(screen == 0)
+			draw_screen(text_dest_x, dest_y, dest_x - text_dest_x, font_size);
+		text_dest_x = dest_x;
 	}
 }
 
diff --git a/src/sys/nact.cpp b/src/sys/nact.cpp
index bc343db..7d93147 100644
--- a/src/sys/nact.cpp
+++ b/src/sys/nact.cpp
@@ -144,8 +144,6 @@ void NACT::mainloop()
 		// 512コマンド実行毎にSleep(10)
 		if(!(sleep_cnt = (sleep_cnt + 1) & 0x1ff)) {
 			SDL_Delay(10);
-		} else {
-			SDL_Delay(0);
 		}
 	}
 }
@@ -323,7 +321,7 @@ void NACT::execute()
 						if(dwTime <= SDL_GetTicks()) {
 							break;
 						}
-						SDL_Delay(10);
+						SDL_Delay(16);
 					}
 				}
 
@@ -356,7 +354,7 @@ void NACT::execute()
 						if(dwTime <= SDL_GetTicks()) {
 							break;
 						}
-						SDL_Delay(10);
+						SDL_Delay(16);
 					}
 				}
 
diff --git a/src/sys/nact_sys3.cpp b/src/sys/nact_sys3.cpp
index e32e4d8..74bf8fc 100644
--- a/src/sys/nact_sys3.cpp
+++ b/src/sys/nact_sys3.cpp
@@ -163,7 +163,7 @@ int NACT::menu_select(int num_items)
 		if(!get_key()) {
 			break;
 		}
-		SDL_Delay(10);
+		SDL_Delay(16);
 	}
 
 	// メニュー表示
@@ -197,7 +197,7 @@ int NACT::menu_select(int num_items)
 			if(abs(my - current_my) > 3) {
 				break;
 			}
-			SDL_Delay(10);
+			SDL_Delay(16);
 		}
 		if(val) {
 			for(;;) {
@@ -207,7 +207,7 @@ int NACT::menu_select(int num_items)
 				if(!get_key()) {
 					break;
 				}
-				SDL_Delay(10);
+				SDL_Delay(16);
 			}
 		}
 
@@ -442,9 +442,9 @@ void NACT::cmd_a()
 			if(get_key()) {
 				break;
 			}
-			SDL_Delay(10);
+			SDL_Delay(16);
 		}
-		SDL_Delay(100);
+		SDL_Delay(30);
 		for(;;) {
 			if(terminate) {
 				return;
@@ -452,7 +452,7 @@ void NACT::cmd_a()
 			if(!(get_key() & 0x18)) {
 				break;
 			}
-			SDL_Delay(10);
+			SDL_Delay(16);
 		}
 	}
 
@@ -725,7 +725,7 @@ void NACT::cmd_k()
 				return;
 			}
 		}
-		SDL_Delay(10);
+		SDL_Delay(16);
 	}
 	if(cmd != 0 && cmd != 4) {
 		RND = val;
@@ -741,7 +741,7 @@ void NACT::cmd_k()
 			if(!(val = get_key())) {
 				break;
 			}
-			SDL_Delay(10);
+			SDL_Delay(16);
 		}
 	}
 
@@ -1306,7 +1306,7 @@ void NACT::cmd_y()
 					if(dwTime <= SDL_GetTicks()) {
 						break;
 					}
-					SDL_Delay(10);
+					SDL_Delay(16);
 				}
 			}
 			break;
@@ -1397,16 +1397,7 @@ void NACT::cmd_y()
 				Uint32 dwStart = SDL_GetTicks();
 				for(int i = 0; i < 16; i++) {
 					ags->fade_in(i);
-					Uint32 dwTime = dwStart + param * 1000 / 60 * i;
-					for(;;) {
-						if(terminate) {
-							return;
-						}
-						if(dwTime <= SDL_GetTicks()) {
-							break;
-						}
-						SDL_Delay(0);
-					}
+					SDL_Delay(dwStart + param * 1000 / 60 * i - SDL_GetTicks());
 				}
 				ags->fade_end();
 			}
@@ -1418,16 +1409,7 @@ void NACT::cmd_y()
 				Uint32 dwStart = SDL_GetTicks();
 				for(int i = 0; i < 16; i++) {
 					ags->fade_out(i, (cmd == 41) ? false : true);
-					Uint32 dwTime = dwStart + param * 1000 / 60 * i;
-					for(;;) {
-						if(terminate) {
-							return;
-						}
-						if(dwTime <= SDL_GetTicks()) {
-							break;
-						}
-						SDL_Delay(0);
-					}
+					SDL_Delay(dwStart + param * 1000 / 60 * i - SDL_GetTicks());
 				}
 			}
 			break;
@@ -1465,7 +1447,7 @@ void NACT::cmd_y()
 						if(!get_key()) {
 							break;
 						}
-						SDL_Delay(0);
+						SDL_Delay(16);
 					}
 				}
 			} else if(param == 3) {