The manual states a battery life of 12-24 hours (depending on volume and lights). To get the best battery lifespan:
Before diving into the button combinations, it is crucial to understand what the BTS766 is. Typically, this model is a cylindrical or rectangular IPX5-rated speaker (splash-proof), featuring dual drivers and passive radiators. It is designed for outdoor parties, beach trips, and garage listening.
To give you the definitive answer for your search query, here is the most reliable path to the PDF:
Abstract The BTS766 belongs to Infineon's PROFET™ (Protected MOSFET) family. In automotive audio engineering, this component is highly regarded ("best" in class for its era) because it solves a critical problem: how to safely drive high-power speakers in the harsh electrical environment of a car without using bulky fuses or relays.
Since the BTS766 follows standard HID (Human Interface Device) profiles, the best manual alternative is a generic Bluetooth speaker guide. Websites like Manuals.plus or Manualslib.com often host the BTS766. Search specifically for "BTS766 Manualslib PDF."