Care to share some example source on how you were able to do that? I am also using IODMACommand. However if the IOBufferMemoryDescriptor::inTaskWithPhysicalMask has the physicalMask set to 0xFFFFF000 (32 bits) then inTaskWithPhysicalMask fails and it wouldn't matter what IODMACommand does since you can't get there.

For those of you looking at this with the same problem, the answer was to add: <key>com.apple.security.temporary-exception.iokit-user-client-class</key> <array> <string>IOUserUserClient</string> </array> to the application's entitlement file. Apple is still trying to figure out why the example code didn't work "out-of-the-box". Thanks!

The IOUserAudioDevice::SetTransportType() function is what generally sets that icon for your device.