om ni undrar så äter jag upp min hatt nu...
"Question: A computer connects via wire to an existing wireless access point/router. Can this wired client send an AirTunes stream to AirPort Express via the existing router?
Answer: Yes, if they are on the same subnet. These are common examples of when it would work:
The existing router is an AirPort Extreme Base Station set up as WDS main, with the AirPort Express set up as WDS remote.
The AirPort Express has joined the network (AirPort or third-party) in client mode.
You have a wired-only router sharing your Internet connection with a separate wireless access point that bridges the network to wireless clients. As in the two examples above, the AirPort Express would be either a WDS remote or in client mode."