I had the same issue with the same model laptop and card/router combo. That dlink combo is a POS. I returned it and bought the linksys one, it worked fine. FYI I returned two dlink ones...I would also switch channels, and try moving...
Did you happen to see how to swap out the cd rom? I want to install a DVD+R drive in it, I have the s109 also...if you have any ideas on how to remove it, let me know...