Upmarket shoe brand On Cloud is being sued over its trainers that make 'embarrassing' squeaks with each step.

The Swiss shoe company, which is publicly listed in New York, is facing a class action lawsuit for allegedly refusing to refund disgruntled American customers for the noisy footwear.

On said the 'CloudTec' sneakers, which cost around 200 USD, were made with holes on the soles 'to provide cushioned support when wearers land'.

But the complaint filed on October 9 claimed the design only caused inconveniences, especially for nurses, as the sneakers cause 'a noisy and embarrassing squeak with each and every step'.

The lawsuit said: 'No reasonable consumer would purchase Defendant's shoes — or pay as much for them as they did — knowing each step creates an audible and noticeable squeak.'

The plaintiffs also alleged that On has declined to provide refunds for the noisy soles, which it classified as 'normal wear and tear' and not a production defect.

Similar complaints have emerged on social media from users of the shoes.

One British customer who bought a pair in London said the squeak started after wearing them only a dozen times.

They said: 'I bought the On Cloudroam Waterproof trainers for 180 sterling last Christmas, and at first I was really pleased with them because they were so comfortable, even if they were more expensive than other brands, and there were a few blemishes in the finish.

‘I had only worn them about a dozen times as I wanted to save them for hiking, but then, after six months, a squeak developed in the right sole. Then the squeaks in the left side.

'It was pretty embarrassing. The squeaky sole was so loud that everybody could hear it when I walked. It's definitely not normal.'

The brand is traded on the New York Stock Exchange as On Holding. Shares in the company are down 37 per cent since January.