How can I correct distorted sound?

Sound Forge and iZotope RX both have tools to repair distorted audio. You can download the trial versions and try it yourself or post a link to the clip (use Dropbox or other file sharing site) and I'll be glad to try as I have both.

Mike

Most NLEs, including Final Cut Pro X and Premiere Pro, have basic sound correction filters. For more extensive correction, you may need a dedicated audio program, like Audition.

If the distortion is clipping, which results from recording levels set too high, you are probably out of luck.