I have two groups of Yongnuo flashes, the YN-560 IV, a YN-560-TX controller, a RF-605C wireless flash trigger transceiver, and a Sony A7R.
Group A contains the main light (two or three YN-560 IVs), while Group B contains a back light (one YN-560 IV). An RF-605 transceiver is attached to the hotshoe of the camera and a shutter release cable to the camera's S2 connector. The RF-605 is set to TX mode.
When I push the button of the shutter cable all flashes fire, regardless of what grouping is preset on the transceiver. Even if detached from the hot shoe, the transceiver fires all flashes in all groups.
Controlling the power and zoom parameters of the groups works as expected, but firing does not.