Sounds like it could be voltage droop. I get this sometimes if I use certain USB ports (even two different ports on the same motherboard) when one port is connected by a different quality cable than the other inside the machine. Just a poorer quality cable or port, but certainly not "the wrong type".
The one posted by
LSainsbury above should be better, you could also try a different USB port (ones on the back of a machine work better as they're directly connected to the motherboard) or powered ports on an external device (e.g. monitor, USB hub, etc.)