Is there a button or menu setting that can turn image stabilization off?

IS has stopped working on all of my IS lenses and I can't figure out why?

The short answer is no.

It sounds like a fault on your lens mount. Has it been bumped or dropped? Anyway, time for a service...

Thanks Liam, it hasn't been dropped but I have been using it continually for about three hours a day for three weeks. I've had it since around November so I think its still under warranty,

I have another day or two on the project I'm on and I'm hoping to finish that before sending it in.

Thanks

Maybe dirt on a contact?