Sweet summer sounds are coming back downtown as the Brookhaven Summer Concert Series returns, beginning this Friday. On May 15, Brookhaven native Sam Mooney will take the Railroad Park Stage at 7 p.m. A singer-songwriter-musician, Mooney is known for piano-driven pop-fusion. On June 19, perennial favorites Mike Rob & The 601 Band will perform. Known for their classic soul sound, the band won Best R&B Artist/Group in 2018 at the Jackson Music Awa…