Can't get TTL to work with Canon 430EXII
I have 3 new V6 transcievers. I have a V6 unit on the hot shoe of my Canon 1DX. I have another 6 feet away with a Canon 430EXII mounted. They both have newly updated firmware V1.1.018 installed. The camera mounted unit is set to TX and indicating TTL PASS-THROUGH. The remote unit with the flash is set to RX. They are both set to Canon 430EX. After taking about 50 shots, I've set the flash unit to both TTL and manual. New batteries. Sometimes the flash fires; sometimes not. When it does, sometimes the image is badly overexposed. Sometimes it's underexposed. No continuity. In manual flash mode, it's doing what it's supposed to do. Please tell me what I need to do to get the TTL working well.