Hi, I just got my new MBP today. So I tried to enable boot chime as I saw in many articles. By typing sudo nvram BootAudio=%01 in terminal. Everything went well, no error shown on terminal. But it didn't work, tried to reset SMC and typed command in terminal already. Still not working. Audio in system pref is working perfectly not in mute mode. Any idea what I should do? BTW. I've tried to disable auto-boot, it works.