Using the latest version of Platinum...  After working fine for awhile, after hitting play, the transport will move and will not stop with the space bar or transport button.  Audio will not play.  It does not lock.  Mouse works, buttons depress (they don't do anything), save works (luckily).  I need to Alt-Ctrl-Del to shut down Sonar.  Just restarting Sonar vs rebooting doesn't seem to make any difference. 'Stop audio engine', Esc, doesn't do anything.  (Using Focusrite Scarlet 2i4).
Any suggestions?

On all your projects? If so I'd try doing a System Restore to the point just before you installed the new update, check if it's working and if so then maybe try downloading/installing the update again. If the same thing happens then I'd report it to the Bakers along with your system specs so they can see if there are any new conflicts with your gear in that update.
 
Good luck.

Had the exact same problem with a Focusrite Scarlet 18i20. That was the final straw in my month-long attempt to get it to work right on my system. Swapped it for another interface and the problem is gone. It must be some type of driver issue with the Focusrite stuff for certain builds. Which driver version are you running? I had tried both 4.15 and 4.26 (beta) but had the same problem with both after a while. I am also running Win 10 64 on an Intel PC.
 
Edited to add I wonder if any of this is tied into when the bakers introduced the MIDI note chase feature. That's a guess on my part so please nobody take it too seriously 'cause I honestly don't know how that would be a problem.
 
 
 
 

It might just be my current project.  Will spend more time on it this weekend.
 

I have a Focusrite 18i8 and its been solid here.
It could very well be a corrupt project, have you tried another ?

Since my last post I have had this happen again on a different PC with a different USB device, starting to think this is either a project issue or a SONAR issue. It happened on my home PC with the Focusrite using SPLAT on Win 10 64 bit. And now just 2 days ago on my work PC running SONAR Professional on Win 7 64 bit. This was using a Steinberg USB device. Had to shut down SONAR with task manager, reopened the project and everything was fine. But it's odd that the OP has this issue, and I've had it as well on different PCs. Something to keep an eye on.
 
One thing I do with all versions of SONAR is under Preferences/Audio/Playback Recording is set the Fade on Start and Fade on Stop values to about 10-15 ms. Wonder if that has anything to do with it.
 
PS I apologize to Focusrite for blaming their product.

SH
Using the latest version of Platinum...
Any suggestions?

emwhy
Edited to add I wonder if any of this is tied into when the bakers introduced the MIDI note chase feature. That's a guess on my part so please nobody take it too seriously 'cause I honestly don't know how that would be a problem.

Something to try in both cases is roll back. This may help establish if the problem is as a result of an update in SONAR.
 
Also referring to the "latest" version is not very helpful. Does that mean the 2017.04 Early release or the 2017.03 Production version? My preference when identifying a version is the full version info from the about screen. The current early release is 23.4.0.31 x64. That and knowing if it is Home Studio/Artist/Professional or Platinum helps fully identify which version of SONAR the question is about.

For me it's 2017.03 of Professional, but the problem in SPLAT started in 2017.02. Have not had the issue of late with SPLAT, just cropped up in Professional two days ago. One other note, neither project had MIDI for me just audio.
 
 

In this case it is not clear why one machine is running Professional and the other is running Platinum. Unless both were retail purchases and not an upgrade from Professional to Platinum, why not run Platinum on both machines? There is no advantage to running Professional if you only have one license. If there is no MIDI, it would not seem MIDI chase could be an issue.

(Using 2017.03 Platinum)  Not sure what's going on....
With my Focusrite 2i4 I played other projects, no problem.  Then the questionable project had transport 'lock' in about 2 minutes.  Disconnected Focusrite and used built in sound card (SoundBlaster) and that project worked fine as did a few others.  Reconnected Focusrite and now questionable project plays fine.  Several edits, and things that used to cause problems didn't.  Did this only about 10 minutes and 20 edits.