amp sub proplems

[Gazza1379]

So installed sub amp and wiring kit but not getting any sound, as far as I know all the wires are where they should be, ive tested the sub and amp in another and work fine so I know it's not that, have tried to ground it in other places but still no luck, I know power is getting to the amp as I used a electric tester and there's power there. Hoping someone can see something that I can't because I'm struggling to find the problem. Cheers 

[Scoobyghost]

Have you tried a different radio? May be an issue with the RCA sockets.