Have Fluance RT83 going to Fosi X4 phono preamp to yamaha rxv800 receiver to speakers. Went to replace the yamaha receiver with Fosi BT30D. Hum introduced. Made sure cables secure and no interference nearby. Attached ground from TT to phone preamp and TT to BT30D. still hum. If I use a Denon Dp300F TT no hum (though Denon TT does not have ground connection). Looking for other suggestions on how to minimize hum.
