Stoffwechsel was a side-project during the time of Feeling B.
The only released songs are "Der Zug" (recorded 1987) and " Fly, Fliege, Fly" (recorded 1989) on Spannung. Leistung. Widerstand. Flake was not playing on Fly, Fliege, fly and the song was later released on Trötsch's solo album Le Petit Orkos. Der Zug was performed live on 22.09.2006.
Note: only listing performances after being inactive due to Rammstein