This even happens in Safe Mode! That means it's not an app but in case it is, here are the apps i recently installed :
Ultimate custom widget (UCCW)
MX Player
Eye In Sky Weather
JuiceDefender - battery saver
AirDroid
Pixlr Express
Spotify
ZEDGE
I have the same problem and i was on Omega v34 and just upgraded to v36...Like you, it started a couple of days ago and now today it is happening all the time... I am thinking of updating the bootloader to XXELLA in Odin...