Slider Revolution no sound on Vimeo background video

Hi there,

we have inserted a slider with a Vimeo video on http://karriere-bei-alpenland.de/, which plays in the background. Unfortunately, despite the fact that we have activated the sound option, it is not playing any sound. Please let us know how to solve this issue.

A screenshot of the corresponding slider settings can be found here: https://we.tl/t-2ioXMpd1ze

Kind regards

Ticket