I was writing before that integration for AKAI MIDI keyboards with Sonar is at the same level as with other keyboards. I was wrong!
All devices are affected: MPK, Advance and so Alesis with VIP. In all DAWs.
 
There are 3 features which transport buttons do not have:
1) buttons are sending the fact they are pressed, but not when they are released. So button combinations / long presses reaction is not possible.
2) buttons have LEDs, so when you hit "play" it is highlighted. But that is local only. It has no relation to the transport state in a DAW, that is just an indication "the last button you have pressed was play".
3) buttons can send MMC, fixed CCs or both. There is also a "MIDI mode", but I have failed to find what it is sending (that is default mode, but nothing comes into Control Surface plug-ins... all instruction for all DAWs mention that you have to switch into MMC or CC). Which CCs are used is fixed, unlike all other controls that is not configurable.
 
People continuously complain about that since years (in Ableton, Reaper, etc. forums, where users usually get "everything works as expected" from custom surface integration).

Hi. I have been having issues lately with my AKAI MPK25, and transmitting MIDI messages. Play, Record and RW/FF has stopped working. I thought it to be a Win update problem, but it seems I was wrong.
I use your AZController, but it just stopped working one day. Even tried using your "start over" preset.
Might have coincided with installing VIP3.0 as well.
Not sure what to do about it.
All the best.

Do you see MIDI incoming into AZ Controller (in the "Last MIDI Event")? I guess not...
 
1) Check MPK Transport is NOT in MIDI mode. Select something else, CC or MMC.
 
2) check that Sonar has not mixed MIDI inputs (last 3-4 versions do that). Remove everything in Control Surfaces and insert again with correct IN/OUT. You can start with just reassigning IN/OUT without removing (select wrong, apply, select right), but that not always works. As the second you can dry to disable all MIDI ports and re-enable them. As last, delete corresponding .INI file in Sonar (for some users that was the only way to get MIDI device working with Sonar again).
 

Hi, and thanks for guiding me Alexey.
I do not see any MIDI coming in (Last MIDI Event).
1: It is set to MIDI/MMC. Not sure if that has changed. Will check and see if there is a MMC or CC setting.
2: Ins and outs were correctly set. I have removed and added it as a CS again, but no go.
Will delete TTSSEQ.INI (I believe is the correct one) and see if that makes a difference.
Will report back.
Thanks, and all the best.

Deleting TTSSEQ.INI did the trick.
It's back, sending MIDI messages, that is visible in "Last MIDI Event".
Will try to set it up again, the way I had it.
I might try to add something as well. Perhaps the QuadCurve EQ, controlled by the knobs.
Thanks again, Alexey.
All the best