DuoFone 43-2638 (Radio Shack) telephone recording controller\nThis device has a standard modular jack to plug into the telephone line.\nThere is also a 1/8" (3.5mm) plug for either the microphone jack or the \nearphone jack of an old style cassette recorders. There is also a 1/16" plug\nthat would have controlled the motor, but I have no use for that as I am simply\ninterested in using the audio as an input to my mixer. \n\nI have been experimenting with attaching the tip/ring wires of the 1/8" jack to attempt\nto use this as an input either into a 1/4" line or XLR mic connector on a mixing board \nthat I've had for awhile, but I am always getting an annoying hum no matter what pins I hook it up to. \n\nI've forgotten more electronics than I remember from 50 years ago in school and am wondering\nif anyone knows if I need to install a capacitor or a resistor either in series or parallel\nto make the buzzing go away and just sound normal. \n\nBefore anyone "goes off" about wiretapping laws this would be used as likely the 2nd line \nfor a podcast. I already have TRRS cable to go into my cell phone and have that portion \nworking wonderfully. \n\nAny help will be greatly appreciated.