Got a strange one- 

New Youngnuo 685Flash with built in reciever which works with Yongnuo YN622C-TX flash controller.

All works well off camera when tersting - ie triggers the flash consistantly. As soon as i mount it on the Sony hotshoe, and take a image, it will fire the flash as expected but then the flash link LED remains on in a constant red state and effectively freezes the flash (NOT CAMERA).

I have to power down the flash and restart and then take another picture and the same cycle occurs. 

Anyone have this issue and how to overcome it?