https://wccftech.com/ios-11-4-for-homepod-released-with-airplay-2-multi-speaker-pairing-and-more/

Alongside iOS 11.4 for iPhone, iPad and iPod users, Apple has released a new firmware update for the HomePod as well.

Though some might dismiss the HomePod as an overpriced Siri-enabled speaker, but for Apple it’s a game-changing music-toting beast. Today, the company is updating its software to iOS 11.4, which adds the brand new AirPlay 2 protocol as well as stereo-pairing, taking the speaker’s credentials to a whole new level.