Clyde my VX has been doing the same exact things as you are describing...
It is at the dealership and it turns out it is related to the sensor on the power steering pump (Switch Kit Pressure - Part# 8971883700) that is frayed and dirty.
Called St Charles and ordered a new one to be next day to the dealership for 154.45. Should be fixed today.
Check that out, I'll let you know when I get it back if that fixes the problem.