Hi,
I was playing movies with VLC on my S4 mini (i9195) yesterday. For some of the movies, VLC had very bad audio quality compared to other players (like MX player for example).
The audio quality improved drastically when I switched the Audio method to "AudioTrack (Java)". Both "AudioTrack (nativ)" and "OpenSL ES" resulted in poor audio quality. The issue is easy to reproduce with the files I have.
The sound was bad in the sense that there was additional noise added to the audio track. The kind of noise that you would expect from some very poor quality sample rate conversion or something like it. Wearing headphones, it was audible for both music and voice. I initially thought that the movie files I had were poor quality (like 22050Hz audio track) but instead both seem to have a 48000Hz audio track. I believe there were other files which didn't have issues with the quality. I will try more carefully to spot any significant difference between the files that worked and the ones that didn't tonight.
Regards,
Sven