How to connect chromecast as input to Focusrite Scarlett 6i6?

I have a Focusrite Scarlett 6i6 as an external sound card but also as a standalone mixer (for my keyboard, mic and other instruments). I have two active studio monitors as outputs from the sound card. If I want to play music from Spotify in the monitors I have to have my laptop connected to the sound card via USB. Now I want to connect a Chromecast Audio to the sound card inputs somehow, so that I can listen to music without having my laptop connected to it.

But I cant figure out how to do it. I'v tried using the combo XLR input on the front by adding a 1/4 jack converter to the 3.5mm male jack from the Chromecast, but the sound in the monitors is very low, and it also seems to be only one of the stereo channels...

Do anyone have any ideas?

Inputs on the sound card: https://us.focusrite...nputs-and-outputs

Thanks in advance!

I have almost exactly same question.
I have an 18i8 connected to some pc-spekers throug headphones jack at the front.
I've tried to connect my chromecast audio to optical line-in but it doesnt work.

Just as BroooopDaPish I want to be able to use my speakers even when my pc is turned off with my chromecast audio.
Focusrite Scarlett 6i6 is a USB interface. I8t has 6 input and output interfaces. Click the link for your answer.