I have a NIGHT HAWK RAX45-firmware ver V1.0.16.132, it is 4-5 years old. About a few weeks ago the signal started to buffer a great deal. My wife's phone call started dropping or she could not hear the other person on the live in seconds. We needed WIFI calling enabled because our cell signal is not very good here. Now some times of the day the wifi goes on and off. I have my desktop connected to the router by cable and have never experienced it going out. So I believe the problem is with the wifi. How do I test it if possible being it only happens now and then?