Speaker maker Sonos has prompted anger from customers over a recycling programme for its high-end gadgets that permanently stops them working, forcing users to scrap them.

The US luxury speaker company, which makes internet-connected speakers costing up to £600, introduced a “Trade Up" programme in October. Customers were offered a 30pc discount if they owned a current Sonos speaker that they wanted to replace.

But to receive the deal, speaker owners were asked to put their device into “recycle mode”. Sonos's website warned that speakers would shut down completely after 21 days and that the move could not be reversed.

“It will be cleared of data and permanently deactivated so you can safely recycle,” according to the company's marketing material.

The programme has been criticised by Sonos's customers who claimed it left them with a device that cannot be refurbished or sold on.

The issue was raised by Twitter user Devin Wilson, who works at an e-waste recycler. “We could have sold these, and ensured they were reused,” Wilson said on Twitter. “Now we have to scrap them.”

He added: “This is the only time I've seen a company explicitly brick its own hardware in the name of 'sustainability'.”

According to Sonos's terms, users must “agree that your Sonos product will no longer function as a speaker or network device”. A Sonos community manager told customers: “Recycling the older products is a condition of the agreement for receiving the discount.”