Hajsch is Hans-Jurgen Schunk, one half of PFN, who was also a member of Kontakta (with a lot of others from the Cologne scene, like Frank Dommert, C. Schulz and Marcus Schmickler). His discography is rather small, with over the last 20 or so years only a small handfull releases http://www.hajsch.de/ Read more on Last.fm