Just got the N5 a few days ago and love it. One issue I can't figure out. Phone will sporadically not ring. Also after this happens no missed calls in call log. Running ATT Sim on Straight Talk. Five minutes later same person will call and phone rings. Called Google Customer Service. Acted like they never heard this problem even though there are numerous posts online about this very issue . Only answer they had was to turn off LTE. Any suggestions??