Hi as the title says I am casting from Google Chrome to my Chromecast device which is connected to my tv.
The video is perfect & I can choose to either cast a browser tab or the whole desktop & that works great but the audio only plays on my laptop & is not cast to the Chromecast.

I am using Linux Mint 17.3 Rosa.

If I connect the laptop to the tv with an ethernet cable I have to change the audio output manually to HDMI, I initially wondered if I would find a similar option but I can't

Any idea's please

thanks.

In general, if something doesn’t work in Linux out-of-the-box — and if it doesn’t work after installing the proprietary drivers your Linux distribution provides — (check Mint's driver tool) it probably won’t work at all. If you’re using an older Linux distribution (which you are) upgrading to a newer one will get you the latest hardware support and improve things. But, if something isn’t working, it's likely nothing will help. However if you still want to try can check Chomecast's support page to see if they have additional drivers available.

Thank you.