Some guy had mentioned that perhaps Skype is causing the usage of Wifi so I uninstalled it and I left Wifi enabled (bluetooth is off cause it is useless and broken) I have a ipod touch 2nd gen, 8GB, 128 MB RAM. I didn't even use Skype. SOLVED! PS : I have yahoo messenger and I use it. No problem with this. Not sure what the deal with Skype is.