I opened a ticket in Customer Support from the person where was not able to help, so I abandoned that avenue.
I DO have a workaround, but I should not have to do this - it should stay snapping to clips until I switch off this setting. The workaround is to hit the <Alt> key whenever the snap to clip stops working. It then starts back working ... for a time and then it stops again. The time which is works varies too, and sometimes it works pretty much for the rest of the editing session and other times for a few minutes.
I need this feature to stay on. Any ideas?