It looks very much like Microsoft will debut a portable speaker of some description at next month's Surface launch in New York on 2 October.

The speaker has come to light thanks to a patent listing made public today. It was spotted by Windows United, but long-time Microsoft watcher Tom Warren of The Verge says that one of the designers behind the device is Malek Chalabi, a designer for Microsoft Teams devices. 

That's a nice little nugget and means that it could well be a meeting room speakerphone designed specifically for Microsoft Teams. The other designer named is Dustin Brown who works for Microsoft's labs to "create and prototype forward-looking hardware" says Warren. 

We're expecting several new Surface devices at next month's launch including a new Surface Laptop and Surface Pro as well as - potentially - a dual-screen Surface. Could the speaker form part of a series of audio devices from Microsoft that started with last year's Surface Headphones? 

Or could it be a smart speaker powered by Cortana or even Amazon Alexa? Microsoft is increasingly using Alexa becuase of the relative failure of Cortana to gain traction. 

It could be used as an accompanying device to the Surface Hub, an interactive whiteboard for businesses that comes in 55-inch Full HD and 84-inch 4K variants. 

However, it's most likely that the speakerphone could be provisioned by any Surface device (or any PC) and so it could be bought and used by anybody.