Does anyone know if there's settings for the speaker...
I know some installers recommend wrapping the buzzer to diminish the volume. I giess it can be loud. As to settings, that would be a question to the staff at Tesla Offer. If you check their webpage, you'll see that you can email, but the time to response is long. Much better to use WhatsApp--a chat software. I had no familiarity with it, but was able to easily load it on my phone and PC. Either Warren (customer service) or Raymond (tech support) will respond, sometimes very quickly, sometimes in an hour or so.
Remember that they are on Hong Kong time, so that is like 16 hours ahead of Pacific Coast time (and 13 hours ahead of East Coast time). So when it is 8:00 AM on the West Coast of the US, it is Midnight in Hong Kong (if I've done that right). So time your WhatsApp chat accordingly if you want a chance at a live response. Otherwise you can leave a series of questions on WhatsApp and I find that one of them will usually respond by their next daylight period.