Do i need ground to the amplifier or to the turntable ?

It seems that is bad grounding of the gear, check i everything is conected to ground. I can also be the quality of the cable, Bad cables can produce a lot of noise, try using other cables.

well" for a start, they need to go into a phono socket, this amplifies them.
i take it you bought 2 decks with the intentions of mixing, so you gonna need a mixer.
MIXER & DECKS SET UP:
1.decks into phono channels 1&2
2. black GROUND wires, go to GND screw on back of mixer
3. RCA master / booth Outputs on mixer to AUX / LINE-IN on amp.(not phono)

It sounds like it has bad ground on the RCA input assembly, you should Ohm out the ground of the RCA jacks to see if they are all connected.
How about the sender side (the amplifier) ground?

Try attaching a ground cable between any metal point on the turntable chassis and a screw on the chassis of your amplifier.

See if you can attach the ground wire to a point on the chassis of the device you are connecting it to.

I assume that you're talking about the output from the 2 RCA Phono Jacks? Does this turntable output a "Line Level" signal, or a standard millivolt level 'turntable signal'? If it is an older 'standard turntable', then you need to run it into an amplifier that has a "PHONO" input and ground wire. This will amplify the tiny signal to a 'line level' signal that you can record or run to a computer, etc. If you do not have an older amplifier with "PHONO" input jacks, then you need to buy a separate stand-alone 'phono amp/preamp' that will boost your (tiny 10mv) turntable cartridge levels high enough (.5 to 1 volt) to record on another device. Let me know if that is the case. Good luck.

Try the switch in the other position and see if that fixes the problem. some turntables had a phono level that is different than a standard rca line level input. Also try a different cable if the rca is not hardwired in to the turntable. The cable could be bad. If worse comes to worse upgrade to another amplifier or tuner that has a separate phono input. hope that helps.

What do you mean the RCA cables are'nt grounded? All RCA cable have a ground. What kind are you using? The round metal at the end of the RCA cable is the ground. The silver or outside of the line input on the amp is the ground for the RCA cables. Anyway, that would'nt stop your amp from coming on. I suggest you take a piece of wire and ground it to the amp and touch the metal piece on the RCA cable and see if you get sound. Even if the RCA cable is'nt grounded you would get some type of sound coming out of the amp maybe. If you do it will sound like it's cominf thru a long tunnel, like a reverb effect. I have never heard of an RCA cable not having a ground. ARE you sure you have RCA cables? Let me know and send me a pic if you can of the input of the amp so I can see how you have it hooked up.

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the remote of amp. is not a ground it is a pos.+ 12 vlts look the back of your car stereo red the remote and conect to remote of the amp. if no sign remote of the car stereo conect to the 12 vlts of your bat.

If you're used to playing your vinyl through a hi-fi turntable (and not DJ turntables) then you're probably used to your turntable having a built-in amplifier. DJ decks don't have these and if you plug into 'line' it will come out very quiet. Try plugging into 'phono' if you have it, if not you'll need some extra amplification somewhere between the deck and the speakers (a mixer usually takes care of some of this before it goes into the main amp of the system). Hope this helps. Ad