DMX In The Clear Over Failed Comeback Tour

TMZ broke the story ... an agency called Heavy Rotation sued DMX in March claiming it struck an exclusive year-long deal with DMX in 2011 to book a string of comeback concerts -- but the rapper was a pain in the ass to deal with ... and torpedoed the entire tour.

HR said it lost nearly $750,000 on the deal gone bad. But the booking agency appears to have had a change of heart -- because HR has voluntarily dismissed the lawsuit.