This time in Ask TUAW we'll look at a kernel panic problem, how to change what appears in iTunes audiobooks sidebar, hot to change the Apple boot icon, how to monitor network traffic, how to automatically file downloads and more.

As always your suggestions are most welcome, and questions for next week should be left in the comments. And now, to the questions!

edge asks

I have a Macbook Pro (2GHz Core Duo) running OSX 10.5.1 and sometimes my screen goes completely gray and I get this message: "You need to restart your computer. Hold down the Power button for several seconds or press the Restart button." I have noticed that it usually (not always) happens when I am using either Transmission or Azureus. What do I do?

What you're seeing is a kernel panic, basically a system level crash. As another reader pointed out this may be due to a problem with the Airport drivers when running a bandwidth intensive application like a bittorrent client. Most of the people on that thread suggest that the problems seemed more prevalent with Azureus than Transmission, but as you note even Transmission will generate the kernel panics.

As for what to do: the first suggestion is to go wired with ethernet if you can. If the problem is with the Airport drivers then obviously plugging in would seem to alleviate the problem. One way to do this would be to limit your torrenting to some time when you aren't normally using the computer (e.g. at night) and thus could leave it plugged in to your router. I have one other suggestion as well: limit the number of connections in your torrent client.

tuawgg asks

I could never figure out the Audiobooks item in the iTunes sidebar. It shows 12 items in my library which seem to have nothing in common with audiobooks or with themselves, for that matter. How do i define - or undefine - files as audiobooks so this sidebar item will become relevant???

The only thing that should appear there are either Audible files (extension .aa) or protected MP4s (extention: .m4b). So you can add AAC files to the list by manually changing their file extension to .m4b. However, there are a couple of donationware AppleScripts from Doug's AppleScripts that make this even easier. Make Bookmarkable will perform the file extension for you on selected tracks, while Make UN-Bookmarkable will do the reverse. I would suggest trying out those scripts to manage the Audiobook Source list items.

artifex asks

I had a boot icon editor for my PPC Mini, and changed the default apple image to a happy mac icon. Loved it until I clean installed Leopard, erasing it. I was wondering, is there a similar program or some other method for changing the boot icon on an Intel Mac, too?

Well it looks like an enormous pain in the behind, but I found this tutorial. Needless to say I haven't done this myself, and frankly the payoff doesn't seem worth the pain and risk. Nonetheless, if you really want to do it that should get you started.

Update: In a comment below Yazdgerd points to a much easier solution with BootXChanger.

mathmonkey asks

Under Leopard I've been getting odd 'PC Server's showing up in the sidebar under 'Shared'. I've read that it could be my Airport Express or my shared printer, but I'd love a utility to view the traffic coming through my network. Can I just be a voyeur to any web traffic on my own network? I do have WPA2 set up, but have trusted visitors regularly and don't want to go to MAC address restriction.

You really shouldn't have "odd" PC's showing up if you have WPA2 set up, so you may want to investigate that some more. But to answer your question what you want is a packet sniffer. There are several options on the Mac, but the easiest to use is probably KisMac. A much more advanced option is Ethereal, but you'd have to run it as an X11 application.

Phil asks serially

My first question is about "Folder Actions." I would like to setup a folder action for my downloads folder that automatically moves .abr (Photoshop brushes) files from my Downloads folder into the brushes folder for Photoshop (Applications/Photoshop/Presets/Brushes). I have looked online for tutorials but, couldn't seem to find any. If you could point me in the direction of a decent tutorial or explain how this is done that would be great.

Frankly the best way to do this would be with Hazel ($21.95) from Noodlesoft. It makes setting up rules like this a snap. You can probably do what you want with Folder Actions, but you'd have to write the AppleScript (or Automator action) and if you don't already know how to do that I think you'd be better off with Hazel. Nonetheless, if you want to give it a shot you might have a look at this tutorial.

When I run software update I am told that there is Pro Applications Update 2006-02 available to download. I click install and it downloads the update but then says "the update can't be installed and the package was moved to the trash. To try again, please launch the update from the Finder." But, there isn't a package that is in the trash. Is there a file that says that the update is still needed or is there a place where I can download this update from on the web?

Well yes the update is available here. But I suspect that it's just an error, since surely you've updated your Pro since then. That is, in all likelihood, why it won't install. You can get Software Update to stop prompting you about it by selecting the update and choosing Ignore Update... from the File menu.