Help! My kids are getting bored! (Hot Cords)

We're assembling a new RepRap. Strange problem.. If I plug in the PSU, everything seems okay.. If I just plug in the USB, everything seems okay..

However, if I plug them both in, both cords get extremely hot within seconds. Does anyone have any idea why this could be happening?

It's a standard RepRap i3 Prusa.. (RepRap Guru) The cord from the PSU to the wall seems to be thin where it connects to the PSU, but it's a little strange that the USB would heat up from that. Any ideas?

This post seems to be what I need. Looks like it's time to learn a little EE

Your bolts that hold your PSU in place the bottom 2 to be exact are too long and are shorting your neutral to ground remove the bolts and replace with a M4 8mm.

If you purchased your kit from Reprapguru, call us for the replacements