I've recently been experiencing a phenomenon where certain, seemingly random MIDI notes are not being played back by BFD 3 & BFD Eco, which I use for full studio productions and demo/sketch pad purposes respectively. I believe it began happening around the time I upgraded to Platinum, although this was around the same time I added BFD Eco to my repertoire, so I couldn't say for sure what change started the problem. I don't think this is happening with any other instruments, though drums are the easiest to detect with this sort of thing.
 
While the missing notes appear to me to be random, each time playback is started from a certain point, it seems to be the SAME notes that are dropped on each playback. I would estimate that 1 of every 10 to 20 notes gets missed, but in some occasions I've heard significantly more of them lost. I usually have a few MIDI instruments going in a project, but this happens even when there is only a sparse drum track and 3-4 audio tracks playing back.
 
Yes, this had happened since the Platinum update a few days ago. Has anyone else encountered this behavior? What did you do?

Increase your MIDI Prepare Using Buffer in Preferences > MIDI > Playback and Recording. Try the old default of 500 if it's at the new lower default of 250. A lot of systems don't tolerate that well. If it's already at 500, try 600 or 700. Some users have reported that Platinum needs a larger MIDI buffer than previous releases.

I've had to jack my buffers right up to 2000!
 
If this doesn't work, make sure your Midi notes are short and all of the same length.
I find a length of 60 ticks works perfectly.

Thanks people! I tried implementing this, and it does seem to make a difference, but does not completely solve the problem. I've upped the buffer as far as 10,000 milliseconds and there are definitely a lot fewer misses at that level, there are still ~5 per playback of a project. I feel as if something else might be going on as well ...
 
Jonesy - How do you change the ticks per drum note? I want to try that next.

Go into the prv. Sweep with your mouse on the keyboard to the left so that all notes are selected.
 
Type '60' in the Event Inspector's duration field

Or, in Track View, select all the clips in your drum track, then go to the Event Inspector as above.
 

This happens to me when using drum maps no matter what. I'm using Superior Drummer, SSD4, Drumforge (in kontakt) and other K5 libraries and even a project with Addictive Drums. Raising the buffer did some good, but the problem never went away completely...until I disabled the drum map.
 
I also noticed that it seems to happen after a certain amount of playback. I'm about to finish my project Sonar Platinum project pretty soon and I see I'm going to have to disable the drum map when rendering.

Jonesy - I reduced all the notes to duration = 60 (they had been at 1000), but unfortunately no difference. Thanks for the idea though.
 
Vern - I was hoping this wouldn't be the solution, but it was. Playback became solid when I removed my drum map I spent such a long time constructing. Did you happen to tell Cakewalk about this when you figured it out?

Once you're happy with the drums bounce them down to audio tracks. Then you can delete the MIDI tracks and any MIDI-related issue should disappear.

My approach to mixing is, other than rough mixes as I go along, once everything's tracked I get rid of all the MIDI tracks and just work with audio. Less system load if I decide to add in more effects and fewer console channels to be dealing with.

Vern C
This happens to me when using drum maps no matter what. I'm using Superior Drummer, SSD4, Drumforge (in kontakt) and other K5 libraries and even a project with Addictive Drums. Raising the buffer did some good, but the problem never went away completely...until I disabled the drum map.
 
I also noticed that it seems to happen after a certain amount of playback. I'm about to finish my project Sonar Platinum project pretty soon and I see I'm going to have to disable the drum map when rendering.

This is the first version of Sonar that I've ever had a problem with skipped drum notes and I always use a drum map.
 
Curious. 
 
I'll test this out when I get home tonight. This is a double edged sword - great if it fixes the problem, but I need drum maps for my workflow.