I would say it's a bug! Here's the workaround I've found:

tellapplication 'Audio MIDI Setup' toactivate

On macOS, there is the built-in Audio MIDI Setup for combining inputs and outputs. The Audio MIDI setup will allow you to create an aggregated device. This allows two things: It may help when screen sharing audio isn't included in the Studio. On Mac, you can use the IAC bus to create any number of virtual MIDI buses. This driver can be activated in the Audio MIDI Setup Utility. Launch Audio MIDI Setup and select Show MIDI Studio from the menu. Now double-click the IAC Driver icon and check the option Device is online in order to activate it. You can rename the port if.

tellapplication 'System Events'

tellprocess 'Audio MIDI Setup'

tellmenu item 2 ofmenu 1 ofmenu bar item 'Window' ofmenu bar 1

ifnameis 'Show MIDI Window' thenclick

endtell

tellwindow 'MIDI Studio'

setpositionto {0, 22}

performaction 'AXRaise'

endtell

do shell script '/usr/local/bin/cliclick 235 180'

endtell

endtell

I made use of Cliclick to click the Network button, after finding its position with the cursor you get using ⇧⌘4.

Dec 30, 2011 7:02 AM

Click here to return to the 'Add MIDI device icon to Audio MIDI Setup' hint

If you want your icon to look nice and pretty, you should create a TIFF with a transparent background. The built-in scaling these icons are subject to can make some pretty ugly results unless you take care to make decent graphics to start with, and the panel expects the image to have an alpha channel.

You can find a wonderful tutorial on how to create your own instrument icons for Apple's Audio MIDI Setup here:

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The world sounds better through headphones.

If you don't like to draw the icons yourself, here is some prepacked artwork:

Audio Midi Setup Mac Os

• Real synth icons (lots of stuff, recommended)

(Found with google query
'Audio MIDI Setup' icon | icons
There might be more but I'm just lazy... Cheers!

3rd link broken

I'd like to share these icons I made with an action script:
TritonRack.tiff, Korg EA1.tif, Karma.tiff, JV-1010.tiff, JStation.tiff, Emu MoPhat.tiff, Kurzweil K2500R.tiff
Download them here:
http://homepage.mac.com/brutus/

Wow, nice work, brutus. Thanks :-)

Audio Midi Setup Mac Default Settings

Audio Midi Setup Mac App

Actually, at least for MacOS 10.5.5, you can create user specific icons (which will move with the User area if you move the account to another machine) by creating a directory path at ~/Library/Audio/MIDI Devices/Your Chosen Icon Library Name/Images and placing the images in there.

Audio Midi Setup Mac Images

Hi, I wonder if anyone can help please , I have been using an Edirol UA-4fx to access logic 8, but most recently my young son has put the midi audio set up icon in the trash ( and its gone!)
I have tried reloading my osx 10.4.11 (mini Mac) platform (both discs) but still there is no midi audio icon in the utility folder and obviously my interface unit is not working..
Any response would be a great help thanks Steve