Muting an embedded vimeo video

Question

On a website I am building I have a vimeo video embedded. The client needs to keep the sound on the video obviously for people that find it on vimeo. However for her website

Answer 1

@Gadss answer works great but I found that you need update the iframe src to include the activation of the Vimeo api. Just include api=1 after the vimeo id.

I've also found that this sometimes doens't work on Safari for some reason.