Ensure the default (dlink) SSID name is changed. Can be anything and not something that's already in use by any neighboring WiFi routers. Under Setup/Wireless/Manual. ok
What wireless modes are you using? Mixed 802.11n,802.11g and 802.11b, but now trying N
2.4Ghz and 5Ghz routers: Try single mode G or N or mixed G and N on 2.4Ghz and single mode N on 5Ghz?
Channel Width set for Auto 20/40Mhz or try 20Mhz only.
Try setting a manual Channel to a open or unused channel. 1, 6 or 11. 11 for single mode N if the channel is clear. 13 for EU regions.
What security mode are you using? Preferred security is WPA-Personal. WPA2/AES Only. WPA-Personal
Some WiFi adapters don't support AES, so you might want to try TPIK only or Auto TPIK and AES. Only AES option is available
What wireless devices do you have connected? Sony Vaio windows 7/ two android devices/ used to connect wireless with ps3 but now i use wire due to this issue
Any 2.4Ghz or 5Ghz cordless house phones or WiFi APs near by? No cordless house phones,or Wifi, But might be something since am in an apartment from neighbors
Any other WiFi routers in the area? Link> Use InSSIDer to find out. How many? yes, 4
If you have any of these options, Try turning OFF or ON Short GI, WLAN Partition, Extra Wireless Protection and HT 20/40 Co-existence if you have it. Also testing with HT20/40Mhz Co-existence enabled will impact results as well. I prefer to use this option OFF. Recommended settings are default. Under Advanced/Advanced Wireless. checking Short GI