possibly a sound card issue, not sure?

[Chris Skarstad]

Hey folks

A while ago, someone was talking about a possible sound card issue, and 
my  girlfriend who is not on this list is having one and she's asked me 
to quiz the gurus.  Basicly, what's happening is whenever she records 
something or broadcasts on the internet, you can hear what appears to be 
a loud humming sound, probably a ground hum. She's using a windows 7 
64-bit laptop, it's a Toshiba satellite of some kind, we're  not sure 
about the exact model number.  Does anyone know     what might be 
causing the issue, and better yet how to eliminate it?   Is this an 
actual sound card issue, or is it something electrical, like how it's 
plugged in? It's plugged into a power strip so i'm not sure if that's it 
or not.   Keep in mind that i'm not an expert in all things electrical 
so i'm not gonna be able to do anything really advanced.  I've heard 
this happen on other laptops, when it's plugged in you hear the hum. 
When they unplug it, it goes away. It wouldn't be practical for her to 
use it on batteries all the time, so we would need to find a way to 
eliminate the issue.  Does anyone know what we can do?
Thanks!
Chris