I bought a Pro 3 about a year ago when in Bellevue. We have been on the road in our Rv for the last two months+ and about a month ago, I couldn't get the unit to charge unless reversing the plug. I could not contact MS through the web site because of bad internet connections. I was successful a few days ago and scheduled a call when we were at a new location and "docked" only to not receive a call. So I am frustrated. I purchased a new power unit via amazon about three weeks ago, and it worked for the first week or two, then had to reverse the plug. How can I get this thing to charge?