Google is telling its home audio vendors that they won't be allowed to add support for smart assistants by rivals such as Amazon's Alexa if they want to continue to use Google Cast, according to Variety. The Mountain View-based company reportedly conducted a meeting in June with 50 of the biggest names of home audio to discuss the plan. The publication adds that Google's talks with OEMs were at least partially successful, with many of those companies planning to unveil their Google Cast-powered smart speakers as soon as next year. From the report:"Google Cast has become a Trojan horse," said one of the attendees, who wasn't authorized to speak on the record with Variety. Google's overtures to consumer electronics makers come at a time of upheaval for many home audio brands. Premium stereo equipment makers, in particular, have seen their sales diminished in recent years by both changing listening habits and a rapid evolution of technology. The move to streaming audio led music fans to massively embrace headphones and cheap Bluetooth speakers. Then Sonos came along and established itself as the market leader for premium Wifi-connected speakers. And finally, Amazon surprised everyone with the Echo, a device that redefined what a speaker does, thanks to smart voice control that can be used to request songs, news headlines, the weather, and even to order a pizza or an Uber.Weirdly enough, Google, Amazon, Facebook, IBM, and Microsoft announced a partnership this week to conduct research and promoting best practices on AI.