[haertig]

Get a flashlight, look very closely into the connector where the plug-in cord goes. Anything in there? Dust, lint, etc.? Get you a wooden toothpick and with the point, clean out any crud in there. I have had a couple of micro USB connectors start "failing", and the only thing wrong was that lint had collected inside the connector from the phone sitting in my pocket. This collected lint was causing the plug to not fully seat and not charge. Check for this especially if your plug-in cord does not seat as firmly as it used to. This is simple to check, and a whole lot easier to correct than replacing the jack. Hopefully you get lucky and this is all your problem is. It doesn't take much collected gunk to cause a problem.

[edit] p.s. - Some toothpicks may be too fat to reach in there. Get creative. Try a piece of stiff fishing line, pluck a bristle off your toothbrush, shave a splinter of wood off of something with your pocketknife, you might have a small cleaning brush that came with an electric shaver, cut off the edge of a photograph into a thin sliver of stiff paper - you're probably surrounded with stuff that would work for the job, and it's just waiting to be discovered. [/edit]