I know this is not Casper issue. Anyone knows how to stop or lower the volume (very loud bong) startup sound in firmware level for good on 27" iMac latest quad core. I have tried numerous apps and terminal commands (yes they work), but as soon as I re-image the Mac it comes back like ghost. BTW this is my testing Mac and I work in a office full of people.....rather embarrassing....
Also I have plugged headphones and still no luck. Bong is loud as ever from main speakers!!?? Help will be appreciated a lot :)
In Mac OS X 10.7.x just use the built in "nvram" command to set "SystemAudioVolume" to 0. The beautiful part is that it can be scripted to set as a shutdown script or periodic to see if it changed.
bash-3.2# nvram -p ... SystemAudioVolume 0 ...
Or for those of us who like XML:
bash-3.2# nvram -x -p <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>SystemAudioVolume</key> <data> MA== </data> ... </dict> </plist>
No start-up chime for me. Normally the system saves the last audio state on shutdown/reboot, but that can be changed with a shutdown script. Be sure to read the man pages or --help to ensure you are setting things correctly and don't cause a rip in the space-time continuum.
bash-3.2# nvram --help nvram: (usage: no such option as --) nvram [-x] [-p] [-f filename] [-d name] name[=value] ... -x use XML format for printing or reading variables (must appear before -p or -f) -p print all firmware variables -f set firmware variables from a text file -d delete the named variable -c delete all variables name=value set named variable name print variable