[brahms117]

I hope this is the right forum -- I'm having a problem with Quicktime and my MOTU 828mkii FW audio interface. After I downloaded the latest iTunes and Quicktime 7.1.3, I had no problems (using a G5 running Panther 10.3.9). Yesterday I did the following:

1. Connected my PowerBook G4 to my G5 using Target Disk Mode
2. On the G5, selected the PB as the Startup Disk
3. Restarted
4. Ran Software Update for the PB (which could now access the G5's internet connection)
5. Transferred 9 GB of QuickTime movies from the PB to the G5 hard drive.
6. Selected Shutdown
7. Pressed the power button on the PB to turn it off from Target Disk Mode
8. Disconnected the FW cable from both computers.

Now, after restarting, Quicktime Player will not play mp3's or movs with sound. I have the Sound Preferences set to my MOTUmkii for output. If I select Built-in Audio, everything works. However, the MOTU is hooked up to my studio monitors and they sound much better than the Apple speaker, or even the Apple audio out.

Strangely, iTunes plays fine through the MOTU. Also, Quicktime MIDI files play fine. Just mp3s or AIFF files produce a high pitched frequency, when played with the Quicktime player.

After resetting the PRAM, a QT movie with sound played fine, and I thought the problem was solved. However, after waking the computer from sleep, the problem returned. Repairing permissions didn't change anything.

Does anyone have any ideas? Oh, Garageband produces no sound either -- just the high pitched whine. I could attach the headphone out to my mixer, but I'd like to fix this problem if possible. Thanks in advance for any help!

[JKT]

Using the Audio MIDI setup app in your Applications/Utilities folder, check your bitrate settings (i.e. the Hz value in the screenshot below):

[brahms117]

Thanks, I checked and my bitrate settings are just like those in the picture. I actually spent 2 hrs talking to AppleCare and we figured out that the problem is with the MOTU interface -- likely got damaged during the connection or disconnection of the PB during Target Disk Mode. There was someone there who had encountered these exact symptoms -- a high pitched whine instead of proper audio through an external FW audio interface.

I'm kind of annoyed that this FireWire problem still exists. I don't read all the Mac boards, but I do remember hearing about something like this over 5 years ago -- that FW ports could simply 'die' because of some current that passes through the port during connection / disconnection. And apparently it doesn't matter if the device and / or computer are powered off at the time. I guess this is just a problem with FW technology.