I hope someone can help with this. I have a Philips 437 turntable hooked up to an inexpensive stereo system which has a dedicated phono input. All worked fine for several years. I then bought a music keyboard and tried to plug it into one of the aux inputs -- barely audible. So I tried a ground loop isolator, and it plays acceptably.
Trouble is, the turntable now issues a buzz through the speakers, which never happened before. The buzz occurs, not when the phono is selected, and not when the turntable is powered on, but only when I flip the switch to lower the tone arm.
I've tried unplugging every input but the turntable with no change. I tried putting a ground loop isolator on the turnable, and the buzz changed to a lower volume, but audible whenever the phono input is selected, not just when playing a record.
The phono input consists of 2 RCA jacks, which appear (to this amateur) to be cheaply made. They are not molded but have screw caps which open to reveal a single wire held by a metal crimp; the wire connection to the plug is not visible. I tried adjusting the crimp to make sure it was not contacting the wire, but nothing changed.
The problem might be coincidental to putting the keyboard in the system, or it might not. You might have broken one of the connecting leads internally when you removed and replaced the phono's plugs. In this case replacing the leads would solve your problem. If the problem is not coincidental, you will need to have the table serviced as there is probably a small semiconductor on the table's underside which would need replacing.
I have the same turntable and the same problem. I just got a new needle, it worked fine for a little while, but there is buzzing every time I lower the arm. Is it the receiver? Would hooking it up to a new receiver help? Or is it the record player?