dvd will not start at Chapter 1 with auto start?

I've made over 100 dvs with dvdsp. Today, the "successful" dvd will not start at the beginning (default Ch 1). It starts about 20 seconds in but varies each time and in different players starts in different locations. I am creating auto start with no menu-as basic as it gets??? I also tried recompressing-same result. I took an earlier file that worked in the past and it showed the same problem. I'm out of ideas. Anyone figured this out before???
Thanks,
Mark