Thanks Andrew snag is it only shows in FS Repaint on the 3D view as a black box but not in any of the Texture or Alpha channels, I will take a closer look to see if I have missed it, if I find it I can delete it but at the moment I have nothing to delete which makes me think perhaps it is being generated by an aircraft config file, if you delete it from the aircraft config you don't get ATC recognizing your call sign, just thought someone other repainter may have met this problem.
see photo

Ron Hollins