Hi,
Have you tried one/all/some of the following:
1. Performed a cold boot of the router?
2. Performed a factory reset of the router?
3. Plugged your PC/Xbox directly into the internet connection?
4. Used Google to see if anyone else has reported this problem?
BTW: using this search
Pluscom problem, I found this
possible answer to your issue.
Hope this helps,
Steve.