I don't know if it's a general problem or not, but I notice that MAD produces glitches in the output at the end of files. For instance, take a short .wav file and cut off the end with a sound editor so that there's still music playing at the end (not silence). Encode to mp3 and play with MAD. Then try the same thing with the decoder in Winamp 2.7x. I tried this test with MAD versions .12.3, .12.4, and .12.5. Maybe there's something about my PC or soundcard, I don't know.
Also, I haven't checked recently, but at the time I was doing a MAD listening test on Usenet, I noticed that the MAD decoder (version .12.2) cut off about 30 milliseconds at the end compared with the Fraunhofer decoder in Winamp 2.666. Maybe the two problems are related.
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