Crystal T

Hi there. I imported a silent video from my downloads into videopad. I am supposed to be recording the narration. As soon as I play the video I hear audio interference. This is my 4th video of this type and I have never experienced an issue like this. The noise continues off and on throughout the entire video. Any suggestions?? PS: I am using a Nano Yeti plug in mic and I have already tried changing the wire to be sure it wasn't that. Thanks, Crystal