To take some load off the main machine (esp when doing audio) I'd suggest recording the actual video and audio on another machine, e.g. via remote desktop. Then it should also be easier to get the actual audio output. Else yeah, go with some virtual audio interface software (Jack, Soundflower etc.)
Plugin latency issues? Phasing on parallel channels? Want to know the real latency of your audio interface? Try the VMG-01!
Professional Audio Engineer at Theater Bremen, Germany • Part Time Programmer