In Sonar Pro 23.8.0 I have a small project with a MIDI track with NO automation (I checked the MIDI events list and there are only NoteOn and NoteOff events).
The MIDI track sends its output to an instrument track with Kontact (v5.1).
Whenever I press play the volume of the Kontact instrument is reset to -6db.
 
Is this a normal behaviour?
What is the correct way to set the initial volume of the Kontact instrument ?
 
 

A midi tracks meter is not reading Decibel information, it is reading Midi Activity.
you need to route your output to an audio source to see decibel levels.

Do you have audio automation (not MIDI automation) on the instrument track?

Click on the "wrench" icon of your Kontakt Instrument.
 
Now, on the top left, click on "Instrument Options".
 
Next, choose "Controller" and uncheck "Accept standard controllers for Volume and Pan" 
 
Best,
Klaus
 

Klaus is correct. I had the same problem, until I did what Klaus suggested. 

Might not be a solution but it's good to know that you can change that master volume slider on the Kontakt instrument and then save that instrument after the change
so that new volume level will be the default for the instrument.

I've seen the same problem posted multiple times over the years.