- Any 2.4Ghz or 5Ghz cordless house phones or WiFi APs near by that maybe causing interferences?
- Any other WiFi routers in the area that maybe causing interferences? Link> Use a WiFi Scanner to find out. How many?
- Check cable between Modem and PC, swap out to be sure. Link> Cat6 is recommended.
- Check ISP MTU requirements, Cable is usually 1500, DSL is around 1492 down to 1472. Call the ISP and ask. Link>Checking MTU Values
I recommend that you have your ISP check the cabling going to the ISP modem, check signal levels going to the ISP modem. For DSL or Fiber service lines, ensure that the ISP is using good working phone or cable lines to the DSL modem and that the phone lines are filtered correctly. I recommend having the ISP service physically check the lines going from the out side to the ISP modem. Connecting to the ISP modem could result in a false positive as the signal to the modem could be just enough to that point then adding on a router, could see problems.
The modem operation is dependent upon getting good data flow from the ISP modem and the modem is dependent upon getting good signal from the ISP Service.If this still fails after and the modem still exhibits problems, the modem maybe faulty and I recommend that you phone contact your regional D-Link support office and ask for help and information regarding this. We find that phone contact has better immediate results over using email.
Let us know how it goes please.