My phone started having connectivity issues recently. It keeps cycling through 4g, 3g, and H. I talked with AT&T and they said there isn't a problem on their end. I tried different modems ( I read this might help), but it doesn't seem to be making a difference. I've uninstalled any apps I've recently installed, but it doesn't seem to be making a difference. Any suggestions? If it's a hardware issue, where could I look, and might it be fixable?