Stop using the first day of class to go over your syllabus and classroom expectations. Use the first day of class to start building the relationships with students you want to endure and nurture throughout the year. Especially if we are online, use the synchronous learning time for building relationships, community, and culture. Deliver the syllabus and classroom expectations asynchronously with Unit Zero.
Unit zero is how I introduce the class to students. It consists of several lessons that walk students through the syllabus, how and why the class is structured the way it is, daily classroom routines, and other "housekeeping" items that we all have.
The head fake (ala The Last Lecture) is that the content is delivered exactly how the mathematical content will be delivered all year. Unit 0 is made of a series of lessons, each designed around a learning outcome, that students work through at their own pace. Students move from one lesson to the next after demonstrating they are proficient at that learning outcome via a mastery check. At the conclusion of all the lessons, there is a "unit test" where students can demonstrate and showcase their learning.
"Your only as good as your record collection." -DJ Spooky