Roberta says she won't be performing her classics anymore because she has a disease. The announcement was made Monday by the singer's rep, who said Roberta has trouble speaking because of her condition. It's not clear how long she's been suffering with the disease. Over time, the disease breaks down a person's nerves and degrades their function. There is no known cure for it. The reason this news is coming out now is because Roberta has a few notable projects on the horizon that might normally require her to do interviews. Next year marks the 50th anniversary of her album, "Killing Me Softly", which is her most famous hit. Flack's version is a direct tribute to Hill's version. Roberta's team says she will continue to pursue musical/creative efforts through her foundation and other avenues.