continous sound when booting

I am using more than 6 year sony model pcg-6n6p with the operating system of window xp professional. Suddenly when i switch on the laptop, after some time when the system starts ( the cap led flashes) the speaker start giving a continuous noise which is annoying. Even if I wait for some time it never stops and window loading continues. I aborted by switching off. When I go for safe mode, there was no noise. Is there aproblem with the software because I have enabled auto update for the windows and last time it updated some of the files in window system. Where I should check?
Thanks
sangunni

 

put headphones over loading to XP

you have probably in sound properties enabled MIC and due to this terrible echo
and when xp loaded change sound properties and disable MIC

 

Thank you for the help. It stopped once I pluck the head phone to the audio out put. I went to volume control panel and muted the mic. sound vanished. I presume that my mic is picking up the sound from the pc. Earlier I am using skype and no problem in using inbuilt mic. Is there any cure for this other than going for external mic?
Once again thanks for the immediate help. I am relived!!
sangunni

 

check here
Audio Setup - Windows XP

xp has 2 option- playback properties - MIC OFF
-recording properties - MIC ON (due to skype ect..)

 

Solved the problem. In the volume control icon, i muted the mic and I found in the control panel "sound reality control" I closed the microphone boost and
also microphone muted. Now no problem. Skype working fine.
I am confused now. How mic works even I mute the mic in the control panel?
Thanks once again for the help
sangunni

 

You welcome.

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