Scripts and variables

Configuration
1

Hello all,

I have the following script:

message_to_google_device:
    alias: "some alias"    
    sequence:
      - service: media_player.volume_set
        data_template:
          entity_id: media_player.nesthub1234
          volume_level: '0.5'
      
      - service: tts.aaa_google_cloud_say
        data_template:
          entity_id: media_player.nesthub1234
          message: "here is a message"

And this works fine. The text is spoken out by the nesthub. However, when I try to replace the text by using a variable like so:

message_to_google_device:
    alias: "some alias"    
    sequence:
      - service: media_player.volume_set
        data_template:
          entity_id: media_player.nesthub1234
          volume_level: '0.5'
      
      - service: tts.aaa_google_cloud_say
        data_template:
          entity_id: media_player.nesthub1234
          message: "{{ myVariable }}"

It no longer works. An error is thrown:

Failed to cast media http://192.168.1.10:8123/api/tts_proxy/da39a3ee5e6b4b0d3255bfef95601890afd80709_nl-nl_f288fdd38e_google_cloud.mp3 from internal_url (http://192.168.1.10:8123). Please make sure the URL is: Reachable from the cast device and either a publicly resolvable hostname or an IP address

Now, the error seems obvious. Of course that url is not publicly resolvable. However I’m pretty sure that this was the url ( internal IP address) I had to use somewhere in the google_cloud setup process. And besides, when using a non-variable text line it works fine…

Any idea what the problem might be ?