N300 ext going red LED light off and on randomly

[dredman]

I have an N300 Ext hard wired to a router as an access point.  It work randomly and the red led light comes on and my items will disconnect and than reconnect.  I have tested the Cat 5 and it is good.  Help

[plemans]

What router do you have? 

What actual extender do you have? N300 is a speed, not a model.