Run medusa in Macvlan Docker --> change IP of the downloadstation

[Dr-know]

I have Medusa running in a Docker with MACVLAN driver (so Medusa has his on IP x.9 ).
The host Docker is IP x.1 but Medusa can not communicate with the host interface, i had to create a MACVLAN interface on the host to communicate with all my docker containers using a MACVLAN interface with IP x.15 (so the Synology server has 2 IP's now.)
but i can not get medusa "talking" to the synology downloadstation, for using the "automated download handeling over API".

Ho can i set the API download handling correct IP ?
Is this possible with a env during container creation ?