I posted this problem last month but the ansewers that I received (thank you both very much) indicated that I had failed to make myself clear. I have three turntables with moving iron cartridges.a B&O 3404, a Denon 62L and a VPI with EPA tonearm I have two preamps with phono inputs...a very vintage Marantz 7T and a 12 year old Coda Fet01 All three

Recently acquired mint (in storage for a number of years) 3404 turntable exhibits very loud hum when turned on but the hum is totally muted while record is playing. My other two record decks are silent when cconnected to my Coda or Marantz 7T preamp. Help Bob in Denver