At home I have a Synology DS211j. It is possible to enable a iTunes service there, that allows to listen to music that is stored on the NAS with a device that is in the same subnet. Here is the documentation:
Enable iTunes service to allow all iTunes clients in the same subnet to browse and play songs or videos in the “music”, “video”, and “photo” shared folder on the server. The server will be listed below Shared in the iTunes window after the service is enabled.
While this works fine when I'm at home and in the same subnet, it is obviously not working when I try to listen to music with my laptop when I'm into my office. Is there any way to make it working even if I'm not in the same subnet?
I have already a dynamic DNS services running so that a domain always points to the DS211j.