[BUG] Audio loosing quality, even changing the bitrate to a bigger value

[Inky1003]

I was converting this video: [attachment=517]
I set x264 and audio = aac 255kbps low complexity(before the source loading)
and when the job was finished, the quality was worse than the source ( Here is the job finished: [attachment=518] )
I tried with better qualities, and the video sounds like the same poor quality. 

Here is the debug output (with only the first try): [attachment=519]
I use the 2018.08.19.1 version in Windows 7 x64

Cu inky