Well Azizi - two white bandleaders who conspicuously used black and white singers and musicians were Artie Shaw and Benny Goodman. Shaw had huge problems when touring in the South - as you can imagine - with Billie Holiday as his vocalist. She left his band owing to pressure from the Southern audiences and the difficulty of staying in hotels, etc. Shaw persevered with a mixed band for as long as he could, and this stance does him huge credit. Shaw, incidentally, was Jewish and an intellectual. His autobiography is worth reading.