The cord is completely solid, keep in mind that the naga has a woven fabric over the copper cabling inside the lead so as to stop and fraying of the cord.
As for the actual socket in the mouse, there's a slot that is made to ensure no horizontal/vertical movement of the plug, so I don't believe that it's a conductivity issue with the lead.
The lights do turn off, so it's either not getting power or the internals have a loose connections.
Mouse has never been dropped and is in perfect condition, not even 5 months old.
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