Never had this before. I do a performance in Komplete Kontrol (NI) (inside Cakelab). I then open up another soft synth -Ivory, or Play or Omnisphere, etc. When I try to record a performance, let's say a piano part in Ivory, the midi notes from the Komplete Kontrol instrument are recorded along with my new piano performance. One would think it has to do with midi out of the Komplete Kontrol somehow sending the notes. I find workarounds, but why does it do this? 

The virtual controller is not a virtual MIDI cable. It is a virtual keyboard. It does not send/receive data from other MIDI devices.
 
Often when MIDI data is coming from unexpected sources it is a combination of "Enable MIDI Output" on plug-in properties and "Always Echo Current MIDI Track" in Preferences > MIDI > Playback and Recording being enabled.
 
I prefer to disable "Always Echo Current MIDI Track" and manually control input echo.

scook
The virtual controller is not a virtual MIDI cable. It is a virtual keyboard. It does not send/receive data from other MIDI devices.
 
Often when MIDI data is coming from unexpected sources it is a combination of "Enable MIDI Output" on plug-in properties and "Always Echo Current MIDI Track" in Preferences > MIDI > Playback and Recording being enabled.
 
I prefer to disable "Always Echo Current MIDI Track" and manually control input echo.

thank you. Will try that. I disabled the Always Echo Current MIDI Track but have yet to find the plug-in properties -enable output. I looked in the plug-in manager.
 
found this -will check the synth rack
 
http://forum.cakewalk.com/Is-There-Anyway-To-Disable-quotEnable-MIDI-Outquot-When-Inserting-Softsynths-m3539913.aspx
 
interesting in all these years I never ran across this problem. Of course, I have only recently acquired Komplete Kontrol.
 
Update. I went to the synth rack and clicked on the proper little clock looking thing, and I see no enable midi output. As one person mentioned, this only happens on his NI instruments. I have not found a way to disable mid output. Please instruct. I can't find an enable or disable midi output -no pull-down menu or prompt
 

Not all synths are capable of sending MIDI data.
One place to see/set the option is on the VST2/3 drop down in the VST standard header

scook
Not all synths are capable of sending MIDI data.
One place to see/set the option is on the VST2/3 drop down in the VST standard header

you're the best man -and kind about it. Much appreciated. It does not go unnoticed. It was enabled. I am hoping this is the answer. Working on 6 projects with about 75 songs. This will ease my frustration greatly as in the creation stage I move along pretty fast. Thanks again.

I was going to reference the very thread that you found already so good find.  Enabling ask this every time will be the permanent solution as it was for me after years of not having that problem also.

Now you have found the feature it can be very useful if you want to record the MIDI output of Komplete Kontrol to a MIDI track. For example you may be using KK's chord, arpegiator or scale functions but want to perform edits on the output.

michael japan
 
Update. I went to the synth rack and clicked on the proper little clock looking thing, and I see no enable midi output. As one person mentioned, this only happens on his NI instruments. I have not found a way to disable mid output. Please instruct. I can't find an enable or disable midi output -no pull-down menu or prompt

The clock brings up the option screen but not the options for any instance of the synth in the synth rack. To see the option for a specific synth in the synth rack - click on the synth in the synth rack then click on the Synth Settings menu, "D" in the image below



 
To insert synths with "Enable Synth Output" disabled by default, use the Add Track menu

or track templates with the plug-in(s) set appropriately.