high pitched ringing

Hello, after a scheduled download of updates from Microsoft, my Dell Diminsion 8400 pc stopped communicating with my Dell photo AIO all in one printer 922. After different approaches to unsuccessfully fix the problem, I removed the Printer program and reinstalled it with the Dell Printer CD. The pc now communicates with the printer and prints.

The problem now is a highpitched ringing I hear in the room where the my Dell PC is. If I leave the room, I do not hear it. When I turn off the PC, the printer and etc., I still hear it.

Can you offer any suggestions?

Thank you,

Bobby