After editing for a while, my playback cursor stops following my mouse clicks. I have to restart VEGAS and then it's OK again. I don't know what it is that makes it stop working correctly. Demo video below (unfortunately missing the transport controls at the bottom, but you get the idea):
For some time, I hammered my longest project from the spinning disk where it's archived and could not reproduce the phenomenon, today. I think I've seen the behavior at times, but being impatient and as old as I am I probably restarted the machine while I went pee or got another cup of coffee which only serves to make my edit sessions even shorter.