Hi, recently I have built an amplifier and now I'm facing humming and buzzing noise from speaker. I have tried to move away the main transformer from the amplifier, and it becomes dead silence, but when I moved the transformer back to the same chassis with the amplifer, the speaker will start buzzing and humming noise, I have tried to use copper plate to cover the transformer, but it just not worked as I expected. May I know what can I do as I'm not looking to add extra chassis for only the transformer, any way to reduce the EF from the transformer?