Android NIC MAC address changed automatically This is very puzzling but my android phone's NIC's MAC address seems to have changed on its own (or at least this is what it's showing).

I have a MAC filter in my LinkSys router and I have given access to only my computer and android phone. I had connected my phone to the access point just a few hours ago. When I tried to connect it now, I couldn't. So I rechecked the MAC filter list (FC:A1:3E:77:57:76) , and I surprisingly found it to be different from what my phone (FC:A1:3E:77:57:F7) was showing. Is this some bug in android? Does this happen? Or maybe the address in my router got changed (which isn't plausible).

PS: Please don't say that somebody must have broken into my router and changed it there, because that's not possible. I use WPA2, and anyways the signal cannot reach outside since outside is very far.

Edit: I guess it's a fault with my LinkSys router, since more weird things are happening. The router is assigning the same IP address to my computer and android phone. Can someone please migrate this question to Server Fault?
Problem is with your phone and not router. Your phones software keeps assigning new MAC addresses every time you turn your wifi on. If you are using MAC address filtering then it will need a static address.