One day I was listening to the album Reanimation by Linkin Park and during one of the interlude songs:
The track has one of the band members - Mike Shinoda - calling his own voicemail number and entering his PIN so that he can hear a message left by a collaborating artist.
This begs the question: What number did he call and what PIN did he enter? I did some searching but couldn't find anyone actually claiming to have reversed the song even after all these years.
I found a GitHub repository that has a Python script called, aptly enough, dtmf-decoder. DTMF stands for Dual Tone Multi Frequency Signaling and is essentially the agreed upon tones that digits on the dialpad make when pressed. Armed with this we can extract the two portions and run the tool:
$ python dtmf.py voicemail.wav 233814 $ python dtmf.py pin.wav 0444#
This means he dialed 233-814 to access the voicemail system and entered the PIN of 0444 followed by the pound key. I don't really understand the 6-digit number being dialed, since usually in the late 90's people would dial their own phone number to access the voicemail, but some carriers did have other ways of doing it.
Do you know any other popular songs that have phone dialing in them? If so, leave a comment and I'll see what they are.