Just like tech support, we'd need some more detailed info than what you've provided.
I imagine that your MP3 clips are recorded with a variable bit rate, which PD is known to have issues with. It would help if you could download MediaInfo and confirm that, or alternately, attach a short sample clip (if it's under 5MB) to your reply using this button:
If the clip is bigger than that, please upload it to a cloud folder and paste the link here so other people can check it on their systems.
YouTube/optodata
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