Color/white balance issue

[MReid]

Depending on what is in the viewfinder the AWB does change sometimes. I shoot in Aperture with AWB all the time.
If it is causing you problems and you are in a consistent light it is better to shoot with a preset Auto White Balance mode....does not matter which one.
Then in Lightroom you can Auto Sync them all at once to a correct white balance.

It doesn't happen to me often so not a problem to me....but easily corrected.