Ouch. Lots of people having speed and cutout problems with that router. See this example from the reviews on Amazon:
I purchased this router a little over a week ago and hooking it up was a breeze. However, I went to speedtest.net and checked my download speed...and I was supposed to be getting up to 20mbps download speed...but I was only getting around .80 mbps. Not good. I hooked my computer up directly to the cable to test and make sure it wasn't my internet provider. I got around 24mbps. So, it was the router. After troubleshooting it for a while over the phone with my brother (who is very good with computers and this kind of stuff...I'm terrible) we were about to call it quits and accept that I received a faulty router. But, we tried one last thing and now I really like this router!
If you are having a similar problem as I described above...try this.
Open up the Cisco Connect program that came with the router. Click on Router Settings. Then, under Other Options click Advanced Settings. This will open a new page. On the menu bar at the top click on Applications and Gaming. Then, in that sub-menu click on the QoS link. The very first setting should be called WMM support. If this is enabled...disable it. Save your settings. And then go test your internet speed. Speedtest.net is a good site if you don't already know another one.
I guess that the WMM setting is there to help enhance games/applications (?), but lots of people have problems with it interfering with the internet speed/causing problems. So, it totally fixed my problem...I hope that this feedback can fix others problems as well!