Thanks for getting back to me.

The problem I am having is switching the PC on, i.e.coming out of sleep mode (issuing the "Power On - Philips - MCE PC - Media Center PC controlled by PCX") whether it is programmed (by default) through the hard power on button or progammed into an activity macro.

I always get the red cross at the top of the TSU9200 display and the "Command Failed" message. If I issue the command with the PC already on then it completes without an error message.

The fact that yours works makes me suspect that the problem may be because my motherboard currently doesn't supply power to the USB ports when in sleep mode. On previous motherboards there has been jumpers to enable this but this Intel board doesn't have any. When your PC is in sleep mode is the red LED still lit on the PCX9200?