I updated to 2016.08 today and notice a strange bug:
 
Whenever I change a note in the piano roll (say, from D to E), when the NOW time reaches it, I still hear the old note (D).  I have to rewind and play the section over again in order to hear the new note (E).
 
This doesn't appear to be related to the MIDI buffers (I use 250ms), because sometimes the NOW time hits the edited note multiple seconds after I make the edit.
 
This happened many, many times today, and I never had it happen before.  It's frustrating, because I have to keep listening to clips multiple times in order to hear changes.
 
Is anyone else experiencing the same problem?

Having MIDI FX plugins in the project will cause that, even if they're not on the track you're editing. This goes way back.

Ah, thanks!  This was the first time I've used a MIDI FX in a project (as an experiment).  I will promptly remove it! :)
 
Has anyone reported this bug to Cakewalk?

I reported a related issue with MIDI buffering when looping with MFX that was a bigger problem for me, and that got fixed some time ago. I don't do much editing during playback, so I never reported this particular manifestation. I suspect it may be an inevitable side-effect of the extra buffering time needed to process MFX. 

Maybe stopping and re-starting, whether by starting/stopping the transport or looping back, is required to "refresh" the processed MIDI data.

Yeah, I'm guessing that yet again I'm running into issues because I do all my Piano Roll editing on-the-fly (during playback).  The Cakewalk developers and/or QA team don't seem to be doing very much on-the-fly editing during their testing, which is unfortunate for me (but perhaps not for the other 99% of Sonar users).
 
Well, at least there is an easy workaround: never use MIDI FX.  I've gone 15 years without using them until this project, so I can definitely afford to ignore them for another decade or so more!  (Although gone are any of my plans to develop my own MIDI FX, which is something that was in the back of my mind...)
 
Thanks for clarifying the issue!

Oh now that's interesting. I only edit on the fly very occasionally (usually drums). I was unaware that Midi FX are bugged in this way, cheers for the heads-up.

Tripecac
Yeah, I'm guessing that yet again I'm running into issues because I do all my Piano Roll editing on-the-fly (during playback).  The Cakewalk developers and/or QA team don't seem to be doing very much on-the-fly editing during their testing, which is unfortunate for me (but perhaps not for the other 99% of Sonar users).

There was a time when you couldn't do any editing in MIDI sequencers during playback; you had to stop, edit, then restart. It was a huge deal when Steinberg announced a version of Cubase where you could do some editing while the engine was still running.
 
This has improved over the years but there are still operations that will either stop the engine temporarily, or require a stop/restart. Whether it's possible to change the MIDI FX architecture in SONAR to get around this issue, I don't know. FWIW you don't have to stop and restart if the section is looped; the data will refresh on the next pass.

I think I've always edited on-the-fly for as long as I used Sonar (and Pro Audio before that).  Of course, I might be mis-remembering.  Either way, I'm so used to edited during playback that I can't imagine enjoying the process of making music if I had to keep stopping playback each time I want to fix a bad note.
 
Maybe I just make lots of bad notes! :)
 
Out of curiosity, are there any DAWs which specialize in on-the-fly editing (ones designed that way from the ground up)?

Even normal MIDI buffering will cause a little of this, but it's usually not noticeable unless you're trying to make changes just a beat or two ahead of the Now time, which is difficult to do with any accuracy.
 
If you're looping several bars, it shouldn't be a big deal, and you can always use the various timeline navigation methods to jump the Now time back without stopping the transport - Prev/Next Measure are my goto shortcuts (non-default keybindings) for this.