Services on remote instance have timeout

[x4N70pHyLL]

My main instance is a container, my remote instance a Pi4 with HAOS.

After setting up the integration, I do get the selected services and entities to my main instance.

However, whenever I call a service, after 10s I get a "Error: Timeout".

I susepected an issue with the service to restart add ons (my main use case) as they are under component hassio which my main (container) instance may not have.

But I do geht the same error when trying it with the restart home assistant service (which is under component core in both cases).

Any ideas?