Project file plays only with shift key held down

[Davidk]

A student of mine appealed for help with a VS project, re 2 issues on the same project file I've never come across before. The 1st is here,
http://forum.corel.com/EN/viewtopic.php?f=1&t=61045
and this is the 2nd. I'm seeking advice as to what might have been the cause.
His vsp project file(multiple clips) played only with the shift key held down.

Long distance (via email) diagnosis indicated his X9 was up to date, and progressive removal of clips etc one by one had no effect on the play result. Eventually he got back to nothing in it, and started again with a new file, which worked/played fine. So whatever it was seemed to be in the bones of the vsp itself.

Any ideas as what he could have done to cause this?

Davidk

[MrJohnny]

David
Cannot help directly, but while playing around with VSx9 this message came up from Win 10 Pro:

This may have invoked the no sound on play-back.

John