ports on 2014 MacBook Pro keep dying

I took my December 2014 Retina MacBook Pro into the Apple Store with the problem but they couldn't reproduce it in the store and asked that I come back with a device that demonstrates the problem. That evening, I spent some time at the office and at home trying to reproduce the problem while capturing it on video. I was able to reproduce it with a DAS Keyboard, Logitech Mouse, a Dell Keyboard and a Dell Mouse (via USB port).

I brought the system and two devices into the store but I started out offering to show them one of the videos. The Genius Bar Tech watched one and agreed to replace the logic board. It's at the Apple Store now and I expect to get it back sometime next week. This problem is most intermittent - it took a fair number of tries to get it to show up these couple of times.

https://www.youtube.com/watch?v=FmQPl2DaUrc

https://www.youtube.com/watch?v=XxG0loDpes8

EDIT:
I got my system back with the new logic board and the problem is still there. I think that I'm just going to live with it as it's typically cleared up with a plug/unplug and reboot. If it becomes a hassle, then I'll get a port hub, either Thunderbolt or USB 3.0.

It appears that this is a problem in currently shipping product. Hopefully they will eventually fix it.

I have been battling the same issue of my USB ports no working when I disconnect from my external monitor and keyboard.

I was able to reset my USB ports by resetting the SMC following the steps on the site below. The USB drive needed to be plugged in when resetting, in my case a USB keyboard. I took a couple tries but worked on the second attempt.

http://macs.about.com/od/usingyourmac/qt/Resetting-The-Smc-System-Management-Controller-On-Your-Mac.htm