Written by Topher Kessler
MacFixIt Answers is a feature from MacFixIt where our editors answer questions e-mailed to us by our readers. This week we have questions on getting Java to load the proper version, per-application sound management, firewire bus troubleshooting, and recovering from a system update interruption.
MacFixIt reader "Chris Sedgewick" writes:
"I am using an application that requires Java 1.6.
I used /Applications/Utilities/Java Preferences to set this as the
default by dragging 'Java SE6' to the top of each pane.
This worked fine until I installed Java for Mac OSX 10.5 Update 4.
Now setting Java Preferences no longer works, and the application
keeps telling me I only have Java 1.5. How can I fix this ?"
Apple stores the java settings in the java preferences file for your host computer. This file is located in the ...:username:Library:Preferences:ByHost directory, and is called "com.apple.java.JavaPreferences.UNIQUE_NUMBER.plist," where "UNIQUE_NUMBER" is a long string of numbers and letters (also referred to as a UUID). Try removing that file and resetting your Java preferences to see if they stick. Alternatively, you can open the file with a text editor such as "TextWrangler." You will see both versions listed in the editor under respect "dict" tags, which also will contain many other attributes for the various versions. Remove the entire "dict" tag and all enclosed items for the unwanted version of java, save the file, and try your Java applets again after relaunching the browser.
MacFixIt reader "Jay Sokolow" writes:
"Is there a way to turn off all sound output other than iTunes?
I like to play music, but alert sounds and sounds from some Safari
sites are annoying. Alerts can be turned off, but I haven't found a
way to disable sound from all Web sites. Is there a way to globally
toggle off all sound output except iTunes?"
Unfortunately, no. In OS X, beyond the global volume, each application's or tasks's volume is governed independently by the application itself. Apple would have to implement big changes to the audio system in OS X to incorporate a per-application mixer of sorts, and while there may be third-party programs that could do something like this, I am not aware of any. The next best alternative would be to write an applescript that could reduce or mute the volume of applications that support scripting, but this would require such support in the applications. This is a unique and potentially useful request, so I suggest you let Apple know about it at the OS X feedback page (no guarantees they'll use it, though): http://www.apple.com/feedback/macosx.html
MacFixIt reader "Gianni" writes:
"I own a focusrite saffire pro soundcard. It is a FireWire device. I
put the Mac on sleep while it was still on and I believe that it screwed
up the FireWire bus because the unit no longer is detected. When
checking system profiler, there is no speed info for the FireWire bus.
All I see when selecting the FireWire is 'FireWire Bus', with no
The wires are fine. The unit is not faulty. I tried the sram reset,
as well as the SMU reset. I have tried powering down and unplugging
everything and that did not work either. I have looked everywhere for
a solution. Can somebody help me?"
This kind of problem can happen from time to time, and could be as simple as a driver malfunction. Have you tried booting into Safe Mode and checking the speed of the bus there? Additionally, try booting off the Leopard DVD and after selecting your language, choose the "System Profiler" from the "Utilities" menu. If the bus is recognized here then it is more than likely a software problem, and you can try reinstalling drivers for the audio device, reapplying the latest OS X "combo" updater, or if worst comes to worst, reinstall OS X using the archive and install method. If none of these bring back functionality of the Firewire bus, then you should take your computer in to an Apple store for servicing.
MacFixIt reader "Lauren" writes:
"Today, when I tried to update my Mac laptop, the process was taking too
long. I couldn't find any way to cancel the installation, so I decided
to turn off my Mac by pressing the power button in the top right
corner of the keyboard. When I tried to restart my laptop, there were
many codes listed on the screen. The screen also dimmed and there
appeared a window in the middle of the screen that instructed me to
restart my computer. However, when I restarted it, the same thing
happened as before. I tried to restart it a few times and leave it
off for some time, but nothing seems to be working. My keyboard
doesn't seem to be responding either. If there are any answers to
this situation please respond with how I can fix it!"
By turning off your system in the middle of a system update, you corrupted critical system components that are now causing the computer to crash every time you boot. To fix this problem, you will need to reinstall OS X. First, boot from the Leopard DVD and perform an "Archive and Install" method of installation. This should get your system running, and after updating again (this time allowing it to continue uninterrupted) you, at most, may need to reinstall a few programs, but should otherwise be able to access your files normally. Be sure to check the box to preserve user accounts and data when performing the "Archive and Install."
Topher has been an avid Mac user for the past 10-15 years, and has been a contributing author to MacFixIt for just over a year now. One of his diehard passions has been troubleshooting Mac problems and making the best use of Macs and Apple hardware both for family and friends, as well as in the workplace. He and the newly formed MacFixIt team are hoping to bring enhanced and more personable content to our readers, and keep the MacFixIt community going here at CNET. If you have questions or comments for Topher or the other MacFixIt editors, feel free to contact us at http://www.macfixit.com/contactResources