This is just a quick technical tip page that some friends asked me to write up online so they can link to it.
I have been trying to set up my camera to be controlled over USB wire from my laptop, with the shutter being fired under the control of the EOS Utility software in live view mode.
This part is simple but the hard part was that I also wanted to have a remote flash fire when the camera shutter was triggered. The flash setup was a YONGNUO 2pcs YN-560 IV Flash Speedlite with 560TX-C Transmitter.
It turns out that trick is that the silent shutter option on the camera body has to be disabled from within the camera menu. The camera also has to be in Tv, Av or M mode, and not auto or creative auto. In auto or creative auto, the option to disable the silent shutter disappears and the flash no longer fires.
I learned this fantastic tip from Charles Krebs on the http://www.photomacrography.net/ website. Big thanks to Charles. :-)