how to restore a damaged voice memo to be able to play it

I've been trying to play a voice memo recorded on an ipod touch 5th gen, but it won't play and won't transfer to my itunes library on my computer (Mac) when I sync it. I presume it's damaged. Resetting the device doesn't fix it and restoring it from backup doesn't fix it because I didn't back it up before the glitch occurred. How can I restore it to it's original version to be able to play it? After the original recording, while playing the recording back, I accidentally pressed the record button again in the middle of the recording, causing it to write over some of the recording, so I tried stopping it from saving the new recording by exiting out of the application and then restarting the ipod and couldn't play the original recording anymore after that. Need the recording desperately for evidence for a court proceeding