The Swedish star has been plagued with several unfortunate incidents in 2014. Back in March, Avicii had to cancel his Ultra Music Festival set due to gallbladder issues. Health concerns quickly resurfaced in April, in which Deadmau5 had to replace Avicii’s Las Vegas Residency. Although we cam only speculate at this time, a grueling tour schedule has likely aggravated these issues and allowed them to be persistent this year. There has been no formal confirmation or announcement from Avicii’s team regarding this unfortunate matter, but we will surely keep you updated on this story as it develops.