Sights and Sounds is your weekly guide to the Bay Area arts scene through the eyes and ears of local artists. This week, guest host Truc Nguyen sits down with Lalin St Juste and Ayikoshi Ehara from the Oakland band The Seshen to talk about three events happening around the Bay this weekend. Ladysmith Black Mambazo on Saturday at 8 p.m. at Freight and Salvage [Note: this event has been rescheduled until August 7] Sudan Archives, Velvet Negroni and Sandu Ndu at Starline Social Club on Tuesday at 7