Is there a bus leaving from Hua Hin center to Bangkok or just the one leaving from the new bus station near the airport?

 

The info online seems to be not updated, and apparently the bus station close to airport is new.

 

I don't want to take a minivan, due to their kamikaze style of driving.

Go to BKS (main bus station) just south of Soi 96. Ticket window on the right. I know there is a bus at 13:00, and more. See https://en.wikivoyage.org/wiki/Hua_Hin