You have a two year RMA warranty, so they should replace the one you have. Did you return the whole unit including the power supply last time (sometimes a crappy powersupply is the issue).
No, the support technician from Zyxel I spoke to originally recommended that I just return it to Buy.com, which I did. So I packed up the entire box and they shipped a brand new one.
What do I need to do to get an RMA? I've already bought a Netgear to replace it, but if I can get this brick replaced with one that works, it will be nice to hold on to.