Here is the first original file.

...and the second.

These two files play gaplessly, but as soon as you encode them to MP3 or MPC, an audible click between them appear, even with Foobar2000 gapless playback.

2 secs at 0dB

UJ

3 secs at 0dB

UJ

2 secs silence, 2 secs at 0dB, 2 secs silence, 3 secs at 0dB, 1 sec silence

UJ

Stripped and butted mp3 files

UJ

Sonogram below of the offending area. File encoded to mp3 with LAME version 3.90.3 MMX using --alt-preset 128.

Decoded file sizes in Foobar2000 are the same as the original.

So, what's the problem, encode into ogg and you'll have your sample gapless.

Yup, can't hear a problem with Ogg.

Edit: I wouldn't know how to check this, but is there something non-standard about the file size of the input wav?

IIRC, zZzZzZz has his own experimental DSP, to smooth the transition in such cases, you can ask him for it.

... which has been verified not to help on this sample.

Waveform artefact produced by imperfect silence detection, compare with the perfect cut and shut in the file 'glitch.jpg' above.

UJ