Seemingly loose keyboard connection
PCK-308UB keyboard functions only intermittently, only when I jiggle the USB cord near where it enters the keyboard. I opened the keyboard and didn't see any obvious loose connections.
Computers & Internet - Adesso - PCK-308UB (DHPCK308UB) Keyboard
Answers & Comments
Probably a broken wire within the cable itself. If you want to try to salvage the keyboard and it is not under warranty, then you can cut the cord about two inches from where it enters the keyboard, strip the wires and connect them where the old connections were. This will require a bit of dexterity in order to accomplish though.