Electrical impulse analysis?

When we use the built-in microphone on our laptop to record when we're not home, it records something that sounds like speech derived from electrical (or electronic?) impulses. It is speech in every detail, but you can't quite hear what is being said - the Mhz etc seem to be all over the place and there is no discernable reason for it to be there in the first place. I have tried using Wavepad but without years of sound experience I can't get it right - Is there a graphic equalizer or other program available that would be better suited to such a thing?? It is definately speech - weird! Please help.