Todesengel

If this is a repost, I apologize, I tried creating this yesterday but don't see my post now. I'm running Win 7 64 bit and Express Scribe is skipping when playback speed is approximately 125% or greater. I've played the same files (.mp3 format) on a Vista 32 bit system and the skipping does not occur. Does anyone have any idea what may be causing this and how to resolve it? Thanks in advance for any assistance,