Hi,
Thank you for your reply, I didn't know there are such an old and common issue on Cakewalk
I activate all MIDI Device when I launch calkwalk and USB port are not changed for long time.
I checked midi device list, and try pushing order button to change orders but nothing changed on screen.
In my case, this is occurred to midi Input not output device, addition to it, this also occurred when I save Project file, unload it, and immediately load it again. Off course all MIDI Devices I use have been connected from beginning to the end and using USB Port are unchanged.
In my environment, when Sonar days, this problem and MIDI Output device problem didn't occur. Recently, newly this MIDI Input device problem occurred. I always activate all MIDI Device when I launch Calkwalk so fortunately I had been able to avoid device swap.
Well, I hope this is newly occurred issue because I suppose I meet all requirements /solutions you gave me...
As additional info, I attached screen shot when the problem occurred. 2 MIDI Input devices are selected. Might be a new problem.