In 2011, which in retrospect was a gentler computer era, I made a piece of software called Volume Pops Pro which installed custom sounds over the system default “pop” sound you get when you increase or decrease the volume on a Mac computer. There was a Funkmaster Flex inspired explosion sound, and an airhorn sound. It was packaged as a package installer that put the files in the correct place. Fun!
At some point in the past 14 years, the installer stopped working. The MacOS operating system has been hardened: there are parts of the file system protected by something called “system integrity protection (SIP)" which prevents making changes to parts of a Mac’s software, including this little pop sound. They also changed the default setting so that instead of playing a feedback sound by default, it’s inverted and you have to deliberately hold down the shift key to hear a feedback sound. Less fun!
My buddy Jivko has asked year after year for a version of Volume Pops Pro that would work again on modern computers. I recently updated the software to make it work. It was a pain: I had to write a MacOS native app, which requires paying Apple a yearly licensing fee in order to sign applications for direct distribution so that they aren’t flagged as potential malware. Apple maintains an under-documented API for listening to global media key events like volume up and down, and so the app listens to these and plays a custom sound in response. There is no way to suppress the system default feedback you get when pressing the “shift” key, though, so I had to consecrate a new key (control) for temporarily muting the custom Volume Pops sound while changing the volume (this is handy in parties or while playing music loud, where you sometimes don’t want to blast an airhorn). There’s definitely a computing metaphor somewhere in here about how something that used to be complicated (put a file on your computer) has now become quite complicated (install a custom app that listens and overrides keypresses, and pay a huge corporation for the privilege).