I installed this little preference pane as a lazy way to shut up the start up chime. It worked... it also killed my keyboard and mouse somehow.

I tried starting up in safe mode to dump it, but even when I get to the safe mode login I can't type. The mouse moves, but doesn't click.

Next was booting using an external firewire drive. No luck! Uh oh, this is starting to get scary if it isn't even limited to the internal startup disk. I mounted the disk from the wifi network on my laptop and I looked for the pane in both the user Library and the system Library and it isn't there. Wtf.

I reset the PRAM and the startup chime is back, but the mouse/keyboard function isn't.

I'm now down to reinstalling the system, but I'm scared even that might not work since external drive booting didn't. Fortunately, both keyboard and mouse DO work when booted from the installation DVD. Any other ideas?

I use that app all the time and it works pretty good... although I will say every once a in while my kb loses function and I have to unplug/replug it to get functionality back. I also have the kb plugged into my display. Don't know if any of it is related to the app in question.

I looked in user library and sys library in the pref panes and the prefs folders and see no sign of it either. It's somewhere else.....

Well, it gets even weirder. I rebooted the machine from the regular boot drive because I was going to use the network to make certain I had everything from it backed up to my Time Machine drive. It sat there for a while while I was dicking around reading on my MBP. I come back to the desktop and everything is working!

I quickly ran the uninstaller for that preference pane. It required me to restart and when it restarted... gah! The keyboard and mouse are useless again! But, this time I sit and wait. After about 4 minutes or so it comes to life. WTF??

I've never seen anything like this. Oh, and its not even USB related. It doesn't seem to matter whether I'm using wired USB or bluetooth connected peripherals.

That's pretty odd behavior indeed. Also, the fact that it doesn't install in the expected location(s) is worrisome. Looking at the dev's site (Japanese) and the comments on the MacUpdate site, it does appear that it doesn't work on all machines.

Now that you uninstalled zap thePRAM.

That is kind of odd though. Look in the /Library/StartupItems folder for ArcanaStartupSound folder and delete it, if it's there is there anything in it? You already checked for the pref pane in /Library/PreferencePanes.

Also check System/Library/Preference Panes and User/Library/Preference Panes

According to Pacifist the pane gets put into /Library/PreferencePanes for this one.

I'd bet there's a Terminal command that accomplishes the same thing.

Yes there is, but it involves remembering a few different commands, too much work.

I prefer going to my Utilities folder and launching Pacifist. As geeky as I am, I still prefer a GUI, that's why I use a Mac.

I just file Terminal commands that I'm interested in maybe using in their own folder. That way, my memory is not required to perform.