You need to set the Negative MIDI Playback Offset in the Preferences menu. Choose Setups>Preferences>MIDI. This capability is provided to compensate for the audio monitoring latency. If you are monitoring the output from your MIDI devices through a mixer, there is no latency. If however, you are monitoring the devices through your computer's outputs the MIDI tracks will play slightly later than the audio tracks. The larger the setting for the Hardware Buffer size, the larger the latency (This can be adjusted on win98 systems in setups > hardware under hardware buffer size. It cannot be adjusted on MAC PTFree systems).By configuring a MIDI offset, you can get your MIDI tracks to play back slightly earlier by a specified number of samples, thereby compensating for the latency in monitoring audio through Pro Tools Free.