I've not used that application. You aren't likely to make it run any "faster". The delay is likely caused by processing the audio. Could be the audio chipset doesn't handle midi or all of the processing is being handled by the cpu which is over loaded.
Assuming all other audio is fine (ie: Windows sounds, audio playback, video playback, etc.), then the problem is a sound card issue, but a software/application issue.
Assuming all other audio is fine (ie: Windows sounds, audio playback, video playback, etc.), then the problem is a sound card issue, but a software/application issue.