Wont work with my 580 ex II at all. Flash works on the camera. I have other flashes 580 EX and 430 ex II and both work on the vello cable. trying to use 580 ex II as master flash to have more control from my camera menu, but wont work with the cable. I can use my 580ex as master flash but with limited control from camera menu. Please give me a hand here. Am I doing something wrong? Thanks in advance.

