This used to happen very seldom, but now it's happening almost every time I try to exit sonar. After I'm finished with a session, I'll save as usual, then close out the session by choosing file -> close. Normally if I wait a few seconds, I can tell that Sonar's done "thinking" and then I can completely close out Sonar by either pressing the X in the top right, or by choosing file -> exit. However, now Sonar just freezes and my mouse cursor turns into that "loading circle" indefinitely. I have to Ctrl+Alt+Del in order to finally close down Sonar. I have no idea what caused this to happen all of a sudden. Has anyone else experienced this lately? 

Check this out:
http://forum.cakewalk.com/Platinum-x64-increasingly-unstable-when-closing-projects-m3210198.aspx
 
if any clues.

lfm
Check this out:
http://forum.cakewalk.com/Platinum-x64-increasingly-unstable-when-closing-projects-m3210198.aspx
 
if any clues.

Thanks for the link. I love almost everything about SPlat, but I really don't like how unstable it's been for me lately. I'm also getting intermittent glitchy audio upon playback which never happened before. 

You may want to try shutting down the audio engine before closing Sonar.  If you have a VST that is still talking to your audio drivers (LONG reverb) when you shut down this could be the result.

If stopping the audio engine makes a difference you may want to look more closely at your VSTs and your Sonar settings.
 
Glen