Headphones Muted

[mattyn1]

My daughter has some of these headphones:

https://www.energysistem.com/en/products/headphone...

Today she has complained there is no sound from them through her ipad - I have checked and they are muted too through other devices. Her Ipad works with other earphones.

There is a button on the lead that pauses and restarts video and also activates SIRI.

How do I in-mute these?

[mannyo]

There is probably a cable fault somewhere between the plug and the earpieces if they do not work with anything else or within the plug itself.