Time synchronization has been added to the MVN Network Sync functionality. To use this feature, make sure to go to the General Settings tab of the Motion Capture Configuration window to add a recording delay if necessary.
Then, go to Options, choose Network Streamer, and be sure to choose Network Sync JSON or Network Sync XML. The format is dependent on the 3rd party software that is listening for either JSON or XML messages. The messages are Start/Stop, file name, file number, and the path for where the data is stored.
When you press the record button in MVN, the JSON or XML messages are sent immediately to 3rd part software like Faceware Shepherd or Dynamixyz Grabber. However, recordings in MVN and in external devices (like headcams) occur simultaneously after the delay. If MVN and the external devices all have a direct timecode feed, the synchronicity should be within a frame.