Thank you for the reply. The DAC 8 is connected directly to the Nucleus with a Quest Cinnamon Cable. The problem arose after I linked the DAC 8 with the Raspberry Pi I have in another room. The day I did the link there were no problems. I turned the system off at the end of the day without separating the link. The next day when I turned the system on the DAC 8 icon had disappeared and was not receiving communication from the Nucleus. Since transmitting the e-mail to you I tried re-booting the Nucleus two more times. Do not ask me why, but, the third time was the charm and all was working well again. I have not had this occur before. Although it has not been necessary before, in the future I think I will turn off the link prior to turning off my system. Again, thank you for the reply. I am optimistic this event was a one-time glitch.