If you're a fan of Sia - and even if you're not - you'll be aware that the Australian pop star is notoriously camera-shy, especially when it comes to live performances.

Most of the time, even when she is performing on TV or at awards ceremonies, she dons the disguise of a huge wig or some elaborate costume so that the audience cannot see her face. It has, for all intents and purposes, become her trademark.

However, it seems that a group of people who attended a recent gig of her's at Park Hayarkon in Tel Aviv, Israel last Thursday were not entirely aware of that fact - and they were so dissatisfied by it, in fact, that they have filed a class-action lawsuit for refunds on their €80 ticket.

According to NME, the lawsuit described the gig as 'lacklustre' and complained that it felt 'impersonal' because she didn't mention Tel Aviv or Israel in her between-song chat. They also complained that the big screens showed pre-recorded footage rather than the stage, which meant that people at the back couldn't see.

The promoter, Ilan Elkayam, said: "We wish to emphasise that the show was extremely successful. We have received hundreds of comments from satisfied fans who thoroughly enjoyed the performance and production. In addition, it should be noted that, to the best of our knowledge, the claim was not submitted against Sia herself.”

It's a strange world - but all we know is that if we filed a lawsuit for every disappointing gig we've been at, we'd probably have our own law degree by now.