Mp3 files playing too fast in ubuntu 12.04

I am using Ubuntu 12.04 version…I Installed the audacity software.But when I play mp3 files,it is being played very fast.Some mp3 files,it is playing for it says some msg like(converting to ffmpeg compatible file").Can you help me to correct the issue.May I know whether I miss any plugin tfor audacity

thanks in advance

Install MediaInfo (it’s available in the Ubuntu repository).
Open one of the files that plays too fast in MediaInfo, then click on “View > Text”.
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