Stopping and starting nuitrack without lag

Currently we’re stopping and starting nuitrack (when the user switches to a game and back) using the Nuitrack.Start() and Nuitrack.Release() functions. This works great and the camera turns off and all, but it lags quite a bit. Any other way to do this? Please note that we do not use the nuitrackmanagerprefab in our scene. We’re doing everything (stopping,starting, starting different trackers etc) ourselves in our scripts.