Sony PCV-L620 - Manual (Page 13)

Locating Controls and Connectors 9
Using a Headphone or Microphone
When you connect a microphone or headphone to your computer,
attaching a ferrite core will reduce electrical interference. Attach the
supplied ferrite core at the end of the headphone or microphone cable
closest to the computer. Wrap the cable through the center of the ferrite
core. The following illustration shows how to attach the ferrite core when
you are using both a headphone and microphone.
✍
The LCD and keyboard cables already include a ferrite core. Do not remove the ferrite core
from these cables.
Plugs connected to
Microphone and
Ferrite core
the computer
headphone cables