Very odd sound file problem in 737TNG

Not really a problem, but here it goes:I have been experimenting with some of the sound files in the 737TNG sounds folder.Once I changed the speed og the sound file PMDG_80knots.wav but I did not save the file after the change; of course I did not intend to change the speed and keep it.I don't know if that event has any influence on my problem which I have discovered now. If it is not a problem, it is at least a strange behaviour:Sometimes when I play the file PMDG_80knots.wav in Media Player, the sound becomes slow (wweeiightywwootss) or quick (eitinutz). Then again, sometimes it is normal speed (eighty knots) ?? It does not happen to any of the other sound files.I have tried to delete all sound files and reinstall PMDG Boeing 737 NG, but this behaviour is still there. I have also deleted the old files from my recycle bin.Does anyone else have the same "problem"? I am just wondering what is the matter with that file. During take off the copilot still announces "Eighty knots" in the correct speed...Yeah, I should just leave it, I know, but...Nico