OGP E980 Vibrate Mode won't stay in vibrate
I've done quite a bit of searching but not able to find anything along the lines of issue I'm having with my AT&T OGP.
Android 4.1.2 Bone Stock. Not even rooted. Running E98010K.
I get to work and put my phone in vibrate mode and after a while it turns the sound on.
I get hangouts notification or email and when I try to unlock the phone, it makes the unlock sound and disturbs the peace at work.
I've had that happen at home too. I would put it in vibrate mode at night and all of a sudden when I unlock, there is sound.
First I though that I'm doing something wrong but since I got this new job, I put it on vibrate during the day and somehow, magically, it turns the sound on.
Has anyone else had this issue or is my phone haunted?
Thanks for your help in advance