Playback scrambling but file not corrupting (2017-04)

Hi all.
 
I have been having a strange issue with the latest update. The projects I am working on contain both midi and audio tracks. At the moment I am editing midi. Occasionally, after restarting the transport, playback will either become completely scrambled, seemingly playing random audio snippets, or repeatedly playing a single phrase from one or two tracks. The transport continues as normal. When this happens I can save the file I am working on. To rectify the issue I must close Sonar and re-open it. If I dont, no matter what project I load sonar will continue to play the random samples - from the previous project! After restarting, however, even the project saved after the audio becomes scrambled plays as normal.
 
Just wondered if anyone else was having issues like this?
 
Thanks!
 
PS....The only thing I have found that MAY be a contributing factor is having a midi track with lyric data open in PRV, but I am a long way from confirming this.