Weird DC Glitch, Interface screws up.

Yea, Im on XP. The only thing that changed was that I encrypted my wireless router this morning. Now I think this must be the issue, because as soon as the second computer in my house that is DIRECTLY connected to my router through a Ethernet cable was turned on, the glitch occured.

So 2nd computer+encrytion = glitch? IMO? But i need advice as to why this is happening.