Aldi do some that get the power from your usb ports so no other power supply needed. Thats where the noise was coming from the other day while you were drinking your coffee
I have a pair on that little PC in the dining room. Loudish but no bass, about £12.99 ish.
First pair stopped working so I phoned up the number on the box and they sent out new ones and did not want old ones back. These might stop working as well soon and I will have to phone them again
