BETHLEHEM, Pa. -

Musikfest's night one headliner, ZZ Top, has cancelled their Aug. 1 performance.

Bassist Dusty Hill is scheduled to have two kidney stones surgically removed later this week.

This has caused the band to cancel six upcoming tour dates starting with Morton, Minnesota on July 25 and ending with Bethlehem on Aug. 1.

If you bought tickets to the concert, contact the ArtsQuest Box Office at 610-332-3378 to request a refund. Those who used cash to purchase their tickets should take their tickets to the ArtsQuest Center box office, 101 Founders Way, in Bethlehem for a refund.

"As a ‘thank you’ to all ZZ Top ticket-buyers, ArtsQuest is waiving all service fees on any tickets they purchase through 5 p.m. on July 25 for any Musikfest main stage acts, excluding the Keith Urban concert, which is already sold out," ArtsQuest said in a news release.

Musikfest does not plan to fill the now open Sands Steel Stage venue for Aug. 1.