MP3 Exporting issue

So here’s my issue.
When I export my final podcast (made of Mp3 recordings) there is this strange ‘whah’ sound, like of like if you cup your hand over your ear and move it back and forth. I can’t seem to figure out why it’s happening. It’s mostly with my own voice audio, not with MP3 files of music I’ve used.
If you’re interested, you can look in iTunes under CQB Radio, and in Episode 3, around the 13 minute mark you can hear it.
Any help would be great.
Thanks,
Tim

I got an idea. Is there a link? I don’t have CQB Radio and iTunes doesn’t let us search.

Koz