Unstable is Adema's second and also final album to feature its original lineup with vocalist Mark Chavez departing from the band after its release and then again after their reunion. It was released on August 12, 2003. It has sold about 400,000 copies worldwide. Its radio single was the self-titled song "Unstable", which also had a music video, but it didn't get very much radio play. Many songs relied more on instrumentation and harmony instead of distortion in comparison to their previous album, but the album also has some of the band's most aggressive work. It was less successful than their first album, debuting at number 43 on the Billboard 200 before quickly falling off the chart.