It has something to do with the way the BN software shuts off the Wifi when the screen turns off. The work-around for this is to install Settings Profile Life and set a profile to turn off Wifi when the screen turns off.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer? | Terms of Service