from what you say ,you haven't secured your wireless access point set up ,leaving your systeme open to anyone
what is thermake / model of your system?
have a read here why it's happening
http://www.pcmag.com/article2/0,4149,844020,00.asp
what is thermake / model of your system?
have a read here why it's happening
http://www.pcmag.com/article2/0,4149,844020,00.asp