Switch doesn't display music_off icon

[Klara]

Hi,
I want to use the switch node with material design icons.
This usually works without a problem, but with the icon "music_off" it isn't working.

These are my settings for the switch icon:

And this is what I get for the off state:

The "music_off" icon works fine when I use it otherwise in a text for example.

[Trying_to_learn]

I am not familiar with the music_off icon.

But for the sake of helping others, could you post the code which will include:

The node that makes the message to be sent into the switch node that doesn't work and an example of there it does.