UI: Fix the scroll credits speed calculation ...

and remove the unwanted auto music volume change

code/ui/ui_credits.c

@@ -106,7 +106,6 @@ typedef struct {
 static wopcredits_t s_wopcredits;
 
 static int creditSeqStarttime;
-static float originalMusicVolume;
 
 static const vec4_t color_programming = {1.0f, 0.6f, 1.0f, 1.0f};
 static const vec4_t color_models = {1.0f, 0.6f, 0.0f, 1.0f};
@@ -385,12 +384,11 @@ static void UI_WopCredits_Draw(void) {
 
 	UI_DrawNamedPic(216, 0, 648, SCREEN_HEIGHT, WOPCREDITSBG); // pictures have 4:3 resolution referenced
 
-	y = SCREEN_HEIGHT - (float)((ysize - 5 * SCREEN_HEIGHT) / TRACKLENGTH) * (float)(uis.realtime - creditSeqStarttime) / 10000;
+	y = SCREEN_HEIGHT - (float)((ysize + 2 * SCREEN_HEIGHT) / TRACKLENGTH) * (float)(uis.realtime - creditSeqStarttime) / 1000;
 	for (n = 0; n < ARRAY_LEN(credits); n++) {
 		if (credits[n].string == NULL) {
 			if (y < -16) {
 				UI_StopMusic();
-				trap_Cmd_ExecuteText(EXEC_APPEND, va("s_musicvolume %f\n", originalMusicVolume));
 				UI_PopMenu();
 				break;
 			}
@@ -433,7 +431,6 @@ UI_WopCredits_MenuKey
 static sfxHandle_t UI_WopCredits_MenuKey(int key) {
 	if (key == K_MOUSE2 || key == K_ESCAPE) {
 		UI_StopMusic(); // -> durch refresh sollte automatisch wieder der normale starten
-		trap_Cmd_ExecuteText(EXEC_APPEND, va("s_musicvolume %f\n", originalMusicVolume));
 	}
 	return Menu_DefaultKey(uis.activemenu, key);
 }
@@ -449,10 +446,6 @@ static void UI_WopCredits_MenuInit(void) {
 	UI_WopCredits_Cache();
 
 	creditSeqStarttime = uis.realtime;
-	originalMusicVolume = trap_Cvar_VariableValue("s_musicvolume");
-	if (originalMusicVolume < 0.5) {
-		trap_Cmd_ExecuteText(EXEC_APPEND, "s_musicvolume 0.5\n");
-	}
 
 	UI_StartCreditMusic();