I received a ticket for SmartMusic crashing on launch from a teacher at one of our schools. This issue did not occur in much older versions of the software. Only in software after the late 2014 releases. Because my troubleshooting did not reveal anything in particular or resolve the issue I opened a ticket with makemusic.
I sent them the crash logs and system information report from the computer in question and they came back with this info:
"If you look at the audio section of System profile you've send me, it will tell you "There was an error while gathering this information." This will commonly cause newer versions of SmartMusic to crash on Mac."
After some experimentation today I discovered that the problem was caused by the "EPSON Projector Audio" kernel extension installed via EasyMP Network Projection that we use with our wireless projectors. System Information shows the same error on all machines I've tested with the software installed.
Unfortunately the uninstallation tool provided with the software does not remove the kext. In El Capitan the offender can simply be removed from /Library/Extensions, in earlier versions of OS X the kext can be found in both /Library/Extensions and /System/Library/Extensions.
The wireless projector software still functions without the sound kext, it is only required for utilizing the speaker in the projector itself.
Once the kext was removed and the computer was rebooted not only did the audio information populate correctly in System Information but the SmartMusic ran properly.