The former Nirvana man will appear on a 'pretty edgy' track on the band's next LP
The band also pull all of their European and festival shows
The band will play eight headline shows in addition to T In The Park and Latitude festivals
Rapper reveals sessions with Portland band
Isaac Brock and co take a break from writing new album to perform
Acts will join Field Music, Iron & Wine and Seasick Steve at the event
Group will join Yo La Tengo and Wilco at the Dorset event
Isaac Brock and co begin the jaunt on July 1
Band set to follow Reading And Leeds Festivals appearences with dates
The band will visit Ireland in December, before hitting the UK