Whats up with my Black ops Connection?

I will have a good three bars for awhile and then it will randomly drop to one. I have open nat type 2. It happens at any time during the day. What could be the cause of these random changes. I have a static ip and have portforwarded all the ports I need. Could my old router possibly be the culprit. Answers WILL be rewarded. O and its not just black ops either.