How do you silence or remove the ‘Droid’ sound message that comes on when the Droid phones reboots? It’s embarrassing, especially during meetings!
Hisettings --> sound & display --> notification ringtone (Choose the "Droid" ringtone )If I'm not mistaken, when you change the notification ringtone, that will change the boot sound too.
Silent Boot is the handy single-use fix. It's an app that mutes your phone when shutting down, then un-mutes after boot-up.
That is all that Silent Boot does. It runs in the background, waits very patiently for your phone to start shutting down, and when it does, sets your system volume to 0/mute. After your phone boots back up, it sets the volume back to what you had it at before the shutdown.
You may disable the start-up sound without having an app running in the background by turning the System volume setting to zero. But on phones with HTC Sense, this option isn’t available in the default Settings screen. Instead, download
an app called Quick Settings (http://www.appbrain.com/app/com.bwx.bequick?install) and use its Volume control feature to turn off the System volume. On the Samsung Galaxy S (Captivate/Vibrant), you can simply do it from Settings > Sound & display > System volume.
Or using Root Explorer http://www.androlib.com/android.application.com-speedsoftware-rootexplorer-Fiq.aspx
You should be able to remove the sound by removing the file /system/etc/PowerOn.wav, or /system/media/audio/ui/Shutdown_128.ogg
PowerOn.wav and just delete wav and reboot the phone and no have any sound. or you can just delete the wav letters
Shutdown.ogg to system/media/audio/ui. and rename and work perfect