Pro tools has a special "Low Latency Monitoring" mode which will bypass any unnecessary processing including plugins, metering, and a few others. This will deliver the sound to your outputs faster (just about in real-time) but will not offer some of the features you may have come to be used to. To use your plugins, simply go to Operations - Low Latency Monitoring, and uncheck that menu item. You can achieve pretty low latency by lowering the buffer size while retaining all of the audio features.