* more AA6YQ comments below

+ On the Configuration window's CW tab, what option is selected in the Keying panel?

Serial port RTS port 4

* What's connected to COM4' s RTS signal?

USB Keying (CW) and

USB Keying (RTTY)

USB Send is connected to DTR

according to the setup in my IC-7300

       73,

               Dave, AA6YQ