Receiver · Pioneer · SX-650

Diagnosis: Hum or Buzz

A low-frequency hum or buzz is audible through one or both speakers.

Safe first checks

  1. Turn the volume down before changing cables.
  2. Disconnect all input cables; if the hum remains, it is likely inside the unit or related to speakers.
  3. Reconnect sources one at a time to identify a source, cable, or turntable ground issue.
  4. Use the turntable ground terminal only for the turntable ground wire; do not defeat the power plug safety ground.

Next step

Record whether hum changes with the volume control and whether it is present with all sources unplugged.