Pictures: http://imgur.com/a/Msjgo

Story: I plugged my Nexus 5 in with a new USB cable in the evening, it made a small "pop" and the Nexus would turn off. I immediately unplugged it and tried turning it on. No success. So I plugged it in with another cable, again, no success. I thought "fuck it, will try in the morning" because I was too tired.

Next morning: Still wouldn't charge or turn on with cable 2. So I plugged in cable 3. Still nothing happened. Then I held all three buttons together for 20 seconds, until I realized that I'm burning one of my fingers which was leaning against the micro USB Port. I saw that the port was beginning to melt, so I panicked and tried to pull the micro plug out of the phone, but it was stuck, so I unplugged the other side of the cable. And now, guess what: After it cooled down, I could turn on my phone, WTF!

So I investigated the port, the back of the phone was melting and the molten plastic glued the plug to the inside of the port, I still can not pull the cable out. Qi charging works fine. Now I ordered a replacement for the micro USB port thingy and I will change it myself. Why no RMA?

1) Because I also had a problem with my power button and went to a non-LG service to solder a new button.

2) I bought the phone from DiTech, which went bankrupt a year ago. So I would have to send it in which would take at least 2-3 weeks, and they may charge me because of point 1.

tl;dr: cable probably killed USB port, tried another cable, which was melting in the port, rendering both, cable and port useless. RMA not possible, ordered replacement USB port board.