Maybe switch to WPA-TKIP instead of WPA2-TKIP/AES. I've had issues with wireless printers/print servers not authenticating correctly/fully when using the higer encryption.
I have a Dlink DIR-655 which works very well. Why not connect it up via ethernet?
Also I had that same router long ago, I ditched it because it kept dying when I put significant amounts of data through it. The 655 chumps along like a warrior, don't think i've hard a single hardware crash with billions/trillions of packets through it each day.
The DIR-655 was one of the models listed by SourceSec as being effected by the HNAP Exploit, more info: http://www.sourcesec.com/2010/01/18/which-routers-are-vulnerable-to-the-d-link-hnap-exploit/