He rose to prominence in the late 1980s/early 1990s as a music radio DJ on south Manchester station KFM,[2] where he worked with Caroline Aherne who had previously developed an Irish nun character, Sister Mary Immaculate.
In 1999 Cash performed uncredited duties as script editor on That Peter Kay Thing, a fact only revealed in 2004 when he moderated the DVD commentary.
As an actor Cash is best known for playing slightly dim-witted and affable working class northern men, particularly Dave Best in the BBC sitcom The Royle Family, which he co-wrote with Caroline Aherne.
They founded the independent production company Jelly Legs, which produced later The Royle Family specials, "The New Sofa" and "The Golden Egg Cup", as well as Sunshine.
[4] In 2015 he directed and executive produced the Sky 1 comedy-drama After Hours, starring Jaime Winstone and Ardal O'Hanlon and written by John Osborne and Molly Naylor.