Rytmihäiriö (Finnish for 'arrhythmia') is a Finnish hardcore punk, thrash metal, grindcore and surmacore Helsinki-based band established in 1988 until 1992, when the band was put on a hiatus. It had a comeback in 1998 with a number of changes in the line-up. The band is signed to Sakara Records, and for distribution Sony.
Band has taken their main inspiration from occultism, devil worship, Finnish mixed drink Gambina and Finnish crime magazine Alibi.