The start-up is on a sound File and disabling it, is usually impossible unless there is and adjustment setting in sounds you might look there but more in likely the sound will stay the same..
Settings >> Sounds Look through the Area..
Put the phone in silent mode before you shut down the phone.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
rds24a That's a great question. What happens if you power up the phone and then press the volume down key?
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I was going to suggest doing the Following from the Link I added below to see if Silence Mode would silence the power up but on my Droid Maxx it does not the start up Droid is still present so I'm not really sure there is an option to silence it.
The First Link is for the ( Ultra Droid Maxx and Mini) the Second Link is for the Droid Turbo. the instructions for the two style of phones are the same.. as far as I could tell
Pushing the volume buttons does nothing during the startup sound. This is really a problem when you're trying to turn your phone on while others are sleeping. On previous Droids, I could either turn the sound off before turning the phone off (and it would boot up silently) or put my thumb over the speaker if I forgot to turn it off. On this droid, however, the speaker is not effectively covered and the boot sound plays no matter what the sound settings are. It is a pretty common complaint across various discussion boards.
I don't know if this App will work or not as I have not Tested it but it does not hurt to give it a Try and as far it looks its a Free App.. here is the Link if you'd like to try it