If you are experiencing latency problems I would suggest that you take a look at your device block size. Larger sizes are less stress on your computer to process but result in greater latency. Smaller block sizes result in more stress on your processor but can yield less latency. Another trick would be to raise the sample rate of the interface you are using to its highest available setting. i.e. if it is only on 44.1kHz, try 96kHz if possible. etc.