Ingerson left the group in November 2004. The band began touring with bigger named acts such as Mastodon, Cephalic Carnage and The Dillinger Escape Plan, and playing large music festivals including the 20 Relapse Contamination tour, the Relapse Records South by Southwest showcase in Austin, Texas, and the New England Metal and Hardcore festival, where the band was profiled by both MTV2 and Fuse. Metal Hammer Magazine named Pretest one of the Top 10 Essential Mathcore albums of all time, while Revolver Magazine ranked the album among the top 20 albums of 2003 alongside of records by Radiohead, Metallica and others. Entitled Pretest, their first album with Relapse was released to positive critical acclaim. The band signed to Relapse Records in October 2002. In 2002, the band released two split albums, a 10' vinyl record with Thoughtstreams and a 7' split with Technician. The new album helped to define and expand the band's sound, and was followed by extensive touring. Shortly thereafter, the band reentered the studio in 2001 to record the No Interference record. The band entered the studio in early 2000 to record their debut album, Contradiction, which was recorded, like every other Dysrhythmia album to follow, completely live with minimal overdubs.
The band was formed in August 1998 by guitarist Kevin Hufnagel and bassist Clayton Ingerson, who were joined six months later by drummer Jeff Eber.
