Use Any Audio File as a Custom Voicemail Message
The iPhone makes voicemail super easy. From recording an outgoing message to listening to new voicemails, it just works. The only thing is, recording an outgoing message never turns out just right because it’s being recorded through iPhone’s tiny microphone. The way around it – upload a custom outgoing message to your iPhone.
To start, you need a suitable outgoing message. The iPhone stores voicemail audio in the Adaptive Multi-Rate format. Unfortunately, neither QuickTime nor iTunes will allow you to export the proper AMR file for this purpose. Instead, Craig recommends using Media Convert to make the conversion. Using the Media Convert site, choose the audio file to be converted and then select the output file. Choose “Adaptive Multi-Rate”, accept the terms, and click “OK”. When you’re asked about a bitrate, use 12.2 kbps and leave the other option unchanged. If everything works, you’ll have yourself an amr audio file.
Now here’s the tricky part. In order to use the custom message, you need to trick the iPhone into uploading it to the AT&T server.
On the iPhone, go into voicemail and tap “Greeting”. Record a few seconds of something and tap stop. Before you tap save, use iFuntastic or SFTP to navigate to /var/root/Library/Voicemail on your iPhone. You’ll see a file called “Greeting. amr”. This is the audio you just recorded. Delete that file and replace it with your custom message which should then be renamed to “Greeting.amr”. Tap “Play” on the iPhone to verify your message works. If it plays, tap “Save” and your custom message will be uploaded to AT&T’s servers.
Now that, my friends, is awesome. Thanks to iPhone Alley reader Craig K. for this tip!