I have an Airport Extreme (the 802.11g version) and two Airport Expresses. The Extreme doesn't seem to give me any issues, but the two expresses, which I use for airtunes and printer sharing are constantly not working.
I will get them working fine and then within a few days they will start to flash yellow and I can't see them in iTunes any more.
I've had them set up both WDS relays and as clients on the network, but haven't found a situation that works.
Ideas?