Should their be an earth/ground wire+fitting from the turntable also/or just switch on/off for play through aux?

antique turntable that had an earth wire on it too. I just found a screw on the back of the turntable and fitted the wire under this screw, It worked a treat and the hum disappeared.

It could be a bad connection of the earth pins to the cartridge. One turntable I had hummed even with an earth connection. I found out that the cause was the connection of the earth wire in a 3 pin plug.

Earthing a turntable.
There are 2 common ways of earthing turntables that have an earth wire as a standard fitting.
If the amp has dedicated phono input there will also be an earth terminal post nearby.
For amps without an earth terminal simply slip the earth wire into the side of one of the turntables rca output connections as you plug into the amp.

Cheers John.

I had the same problem with my Pioneer AVH-P4050DVD

Radio and CD worked fine

DVD would play and I could hear the audio but no video

USB and iPod. It would connect and I could brouse, select and play songs but I would not get any audio even though I could see the track playing, finnishing and moving on to the next one (very frustrating).

Front Aux (Aux 1). I could turn this port on to audio, select it and plus an audio sorce in but no audio would come out.

The solution..
The Pioneer AVH-P4050DVD is odd and different from most other pioneeres in that it has two earth leads that both need to be grounded (2 in addition to the handbreak wire). I had insalled my unit using a toyota - pioneer wireing adaptor I bought from Repco. This adaptor only grounded the wire coming from the corner of the plug (opposite the battery wire). The second earth is located becide the first earth, opposite the ignition wire. If you google pioneer 16 pin wiring diagram it might call this pin BGSENS (pin 13 in the attached photo). With the wireing harness I had this pin was not connected to anything. Once I grounded the second earth (soldered directly to the first earth) everything worked.

Good luck. Hope that helps.

either you haven't earthed the deck to the amp, on the proper ground screw, or your head shell wires are touching.
if the cartage(the thing the needle slots into) unscrews from the tone-arm, try unscrewing it,then putting back on, nice & tight....
if it still does it then it's your RCA leads that go from the deck to the amp(phono cables).
normally you would wire a deck/decks to a mixer first, then from the master out on the mixer to the AUX IN on the amp.

At the back of your mixer you should have a switch to change the frequency for a turntable. Also make sure you have the turntable's earth (ground) wire connected.

Fasten the ground to one of the metal screws that hold the metal(?) cover on.You want to connect it to the metal frame of Onkyo.

there should be a small round connector on the rear of the turntable for the mains transformer supply and the loose wire is the earth/ground connector which should be connected to the screw connection on the rear of your amplifier? just loosen the screw ( usually brass or steel ) on the back of the amp, wrap the thin earth wire around the thread making sure it has some exposed copper ie, strip a bit of the cable and then tighten it back up? good luck

HELLO
This problem is usually caused by the turntable(s) being too near the loudspeakers - a sort of "howlround" effect if you like.
Make sure that the speakers are as far away as possible from the decks and that your cartridges are set up correctly too. On the back of the turntables, there should be a connection for a ground wire, but that should have nothing to do with this situation.
Hope this has helped, and good luck! (:-)

Yes first check is that the Gnd wire from your turntable is connected to the Gnd (ground) post at the back of your amplifier with a good clean tight connection.
If the problem persists, check ALL your hi-fi components mains plugs for earth connections including your turntable, then remove the earth connections on all but one component so that you are left with only item earthed.
What does sometimes cause problems is if 2 or more hi-fi separates are earthed and connected to each other the earth cables along with the hi-fi interconnects form an inductive loop that picks up interferance such as mains hum etc.
Regards John