No Ranging Response received - T3 time-out

This seems to be a common thread with alot of chatter and limited solutions. I recently bought a new Arris SB6190 modem and have had the T3 timeout since the beginning. Two  weeks ago i was out of town for a week and didn't have internet for 4 days. Cox reset modem with no improvement, finally it came on by itself. this morning I didn't have internet until a modem reset. The modem has a whole page of the time out errors, yet after reset, I have full speed. What gives? Thanks