Dumb idiot light?

[chartaxi]

I replaced the alternator two months ago. First with a rebuild. The battery light came on as I left the shop so I went back and had a new one put in. The battery light stayed on and the charge on t…he tester was 14+.Then replaced battery. The light persists with no particular pattern. It comes and goes whether moving or stopped.In every other way this car, a cab with 236k on it, runs beautifully. However I now get feedback through the radio when accelerating or raising/lowering windows.