While listening to the playback when I record a track, I hear some crakling while using Cool edit pro 2. The funny thing is that I used the same echo mia soundcard, but this is a new version of cool edit pro. So I was thinking it could be something that gets wrong. I'm using a P-4 2.4 ghz with 2gig ram. So it's plenty. I discover that inside my PC was a lot of dust.Could be that. Anyway, if someone can help before I change my soundcard.