“The Canadian Opera Company announced yesterday that baritone Pavlo Hunka has withdrawn from singing in its current production of Richard Wagner’s four-opera Ring of the Nibelungs cycle, which concludes on Oct. 1. He will also not be singing in the company’s October production of Mozart’s Cosà fan tutte. Hunka walked out of Ring dress rehearsals eight days ago. At a release party held yesterday at the Four Seasons Centre for the Performing Arts for the singer’s new two-disc set of Ukrainian art songs, Hunka revealed that he has been diagnosed with diabetes.”