There have been issues with running LiveProfessor in the background on OSX.
The solution has been to disable App Nap on the system, as it interrupts audio when the latency is low.
To disable App Napp:
Open the Terminal app, found in the
/Applications/Utilities/ folder
Copy and paste the following defaults string into the terminal, then hit the return key:
defaults write NSGlobalDomain NSAppSleepDisabled -bool YES
Close out of the Terminal and restart the Mac