how to change dax settings and where do I find it

If your talking about the Window device DAX setting then I would recommend you not fool with them.  Doing so without a reasonable level of windows knowledge could lead to additional problems and if you do not know where they are then you probably do not have the needed level of knowledge.  Sorry if this comes across as a bit blunt but I could not think of a nice way to say it and still get the cautionary point across.

However, if this is the case then it seems people are getting success by submitting a help desk ticket and having Tim remote into their computers to fit things.