CNN Films’ “Linda Ronstadt: The Sound of My Voice” is now on demand.

CNN  — 

When Linda Ronstadt found herself struggling to sing, she thought the headphones she was using at the time were defective.

“I couldn’t hear the top end of my voice. I couldn’t hear the part that I used to get in tune,” the legendary artist shared with CNN’s Anderson Cooper in December. “My throat would clutch up. It would just be like I had a cramp or something,” she added, noting that this was the moment she realized something was off with her health.

That was in the year 2000. By 2009, Ronstadt was preparing for what she knew would be her final show. It was in San Antonio, Texas, and she performed songs from her 1987 album “Canciones de Mi Padre,” which pays homage to her Mexican heritage.