many audio editors have tons of filters. Depends exactly what it wrong with your recording. Is it just noise and hiss?

If so then there#'s loads that will likely help you out. I happens to use Adobe Audition personally. I think it's great but then I've not used anything else so can;t really compare too much. It has great noise filtering though. Adobe have a 30 days trial you could download.

Unless anyone else has any other suggestions that is....

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