Home Jambase Full Set Audio: Warren Haynes Joins Bob Weir At 18th Christmas Jam...National Music NewsJambaseMusicFull Set Audio: Warren Haynes Joins Bob Weir At 18th Christmas Jam Pre-JamDecember 21, 2016901FacebookTwitterPinterestWhatsApp Listen to host Warren Haynes sit-in with Bob Weir and an all-star band during the annual Pre-Jam concert in Asheville.