Please help adjust this

Hi all,

This is my first post. I am totally new with Cool Edit 2.1. I have issue as shown in the below photo:

Parts of the sound waves were below the zero lines (where I have the red arrows). Would anyone mind to show me how to bring it back to the zero lines.
I appreciate it!

Thank you, all!
SS

That looks to me like a rather large DC offset. Since I don't have that version of CoolEdit, some of the menus and/or labels might be different.

Under Transform/Amplitude/Amplify there is a checkbox for DC Bias Adjust, which you may want to apply with zero Amplification.

Under Options/Setting/Devices is a check box for Adjust for DC on record.

The real and proper correction is to fix the hardware. Something is probably wrong with the hardware setup or the audio card, including the passivity of bad capacitors.. A properly operating system doesn't usually produce a DC offset.

AndyH is dead on - this is DC offset.  While you can change this in software, you should really upgrade your hardware.  It's almost certainly the result of using a poor soundcard.