The only way I know is to do a factory data reset using the button functions. That would put the volume back to when you first got the phone.
Thank you for reaching out to us. I am sorry to hear that your phone is broken. That is never a good thing to hear. We certainly want to find an option to help with this. With the status of the screen there are few options. The best route would be to try an alternate hard reset http://vz.to/1dJ9CFH. Do you have insurance on this device? Please fill us in so we can review options.
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