I had same problem just last week. It had been about a year since I had used my bench top cable, and I had forgotten that I had to use switch on cable instead of switch on power supply.
I thought something was wrong with TCII, but after a couple messages back and forth from TC, I realized that I needed to shut cable switch, cause he said that part of flash was after switch was off.
I tried it and worked.
I had just forgotten procedure.
Maybe that might help.