This is weird.
Suddenly today i am missing one MIDI-note in Sonar.

I have made rollback to several other versions, and even un-installed and re-installed.
I have an old Sonar X1 and the problem is not in X1.

I use MIDI input from M-audio axiom 61 (USB) and connected to Yamaha Tyros 4 also with USB.
I have a RME Babyface as sound device. Have made no changes to Sonar and none to the keyboards.
I am on a Windows 10 computer.

When i hit that note it mutes all other notes as well.
I can go to Piano Roll and click on the note and then it comes with the sound.

Regards!

.

See a short .

PVK
 
I can go to Piano Roll and click on the note and then it comes with the sound.

From this we know that SONAR can send MIDI out to your keyboard. 
 
First, try increasing the MIDI buffer size in Preferences (MIDI > Playback and Recording > Playback > Prepare Using...) as that seems to solve a whole lot of "hey, MIDI notes are missing" issues. I have mine set to 1500. I realize you haven't changed SONAR or your keyboards, but Windows 10 has changed so you never know..
 
If that doesn't solve it, the next question is does the note get recorded in SONAR? Try to record and see if it shows up in the event list or PRV.
 
 
 

In addition to the above, do a quick check on the events list of the recorded track just in case that note is MIDI-mapped to something you didn't realize. Did you do any MIDI learn functions with that keyboard and SONAR?

mettelus
Did you do any MIDI learn functions with that keyboard and SONAR?

Last week i actually did some keyboard shortcuts. And i did just go back there now and unmarked the "MIDI Enabled" and that solved the case.

Under: Keyboard Shortcuts / MIDI / Enabled

I have unmarked it now, and there you go - i can play the "D"
I was starting to learn to play songs without D :-)

Thanks guys!

mettelus
In addition to the above, do a quick check on the events list of the recorded track just in case that note is MIDI-mapped to something you didn't realize. Did you do any MIDI learn functions with that keyboard and SONAR?

Wow...great catch!