"Pop" at start of file after conversion.

[2fours]

After encoding a wav to aac using this library there appears to be a "pop" sound at the start of the aac file that is not present in the original uncompressed file. You can clearly see this in the waveform:

Uncompressed:

Compressed:

Any ideas about why this is happening?

[timsu]

Not at all. It may have always been there, we just never noticed it because we didn't have silence in the beginning. Feel free to take a look at the code yourself, but I can't think of any reason off the top of my head.