Apple Audio MIDI Setup disappearing icons bug

July 18, 2018 0 By leigh

I recently encountered a weird situation with Apple’s Audio MIDI utility. I run a fairly big rig of audio interfaces and external USB and MIDI musical gear, and so use Apple’s Audio MIDI Setup utility to map the devices that are connected to the various MIDI interfaces.

I have assigned my own icons to each device so I can see a visual representation of each device as it helps in planning the routing and relates more closely to the physical layout of devices. You can add your own icons if you create directories of the form:

~/Library/Audio/MIDI\ Devices/YourIconSet/Images

where you should substitute YourIconSet for each collection of icon images, this can include particular manufacturers, for example M-Audio provide icons for all of their devices, or, since I have several home built devices, I have a directory named “Leighs”. You have to save the image files as .tiff format and file name extension. Then within Audio MIDI, add a device, double click on the icon and then open Icon Browser, and you should see your YourIconSet directory listed as an Icon set.

One day after a crash I was presented with the following display with all the device icons missing.

After checking that upgrading from MacOS 10.12.6 to 10.13.5 didn’t fix the problem, some sleuthing in the defaults revealed for some reason the icon size setting had been reset somehow:

In run:

defaults read "" 'midiIcon.size'

This showed a value of 1.

Experimenting with setting some values showed that 100 was the right size to use. Quit Audio MIDI and then run in the Terminal:

defaults write "" 'midiIcon.size' '100'

Then relaunch Audio MIDI and the expected display looks like:

Hopefully this will save someone some head scratching and time. You could also use this if you want to reduce or expand the size of the icons, perhaps to address visibility requirements for your particular vision capability.