Apple appears to be working on major new HomePod home theater features, including a four-speaker surround sound system and a new "Party Mode," according to code found in audioOS 27 beta 8. References in the software for the second-generation HomePod suggest the ability to tune for a setup with front-left, front-right, rear-left, and rear-right HomePods. The four-speaker surround configuration references automatic room calibration, speaker-position mapping, timing adjustments, bass management, EQ, dialogue enhancement, and different processing modes for movies and music.

For stereo content, the code suggests the ability to either spatialize sound across all four speakers or limit traditional stereo playback to the two front speakers. The files also reference a new tuning system called "Forklift" that combines two second-generation HomePods with two speakers using an unidentified AID12007 hardware family, suggesting a future HomePod mini or third-generation HomePod. Additionally, Apple is working on a new "Party Mode" feature for stereo-paired HomePods that applies a more diffuse sound field to spread audio evenly across a room.

These features indicate Apple is testing them, but whether they will be released remains to be seen.