Are you using CM Security? I suddenly saw the same unexpected behavior recently (with WiFi at least); finally figured out my antivirus/security had added it as an option (Settings, WiFi Power Saving--turn Off) in a recent update, and enabled it by default(!?).
Perhaps try checking out the settings of your security app(s), or any apps that might turn things off to extend battery life. If it's a new behavior, you might start with apps listed under Recent Updates in your My Apps list on the Play Store. Good luck.
06-13-2015 05:00 PM