I just noticed today while driving that the alternator will go from 14.5v to 13.1v and sometimes get as low as 12.7v, then suddenly jump back up to 14.5 for a while then drop down again. Battery is a new XSpower D3400R, I tested the voltage when I got home with the car off and the resting voltage is 13v. Is this a sign my alternator is going out?