The Voicemail database contains metadata about each voicemail that is stored on the device, which includes the sender's phone number, callback number, timestamp and message duration, and more. The voicemail recordings are stored as Adaptive Multi-Rate (AMR) audio files that can be played by any media player that supports the AMR codec (for example, QuickTime Player). The Voicemail database can be found under /HomeDomain/Library/Voicemail/voicemail.db.