OMG, I am so glad i'm not alone with this issue. I would really like to share with you all my aggravations with at&t and samsung. I have been dealing with this issue about one month after buying my S6 on launch day. I have had 3, S6 replacements and they all do the same thing. I have poor signal strength where I work in a major city in CT.I have spent numerous hours on the phone with both samsung and at&t and they are almost no help. They both either will not admit or know there is a wide spread issue with this phone. I have gone though about every trouble shooting step there could be and nothing has fixed this issue with either 3 devices. Finally I complained so much that I talked with a regional manager ,who talked to his manager and got them to even swap me into a note 5. (that wasn't easy,by the way) I thought my problems were over, but sure enough the note 5 is doing the same exact thing. This is extremely annoying, I am ready to give up on samsung products, I have never had these issues before and i have owned every galaxy since the s3.