Option to avoid audio re-encoding

[maxdrake69]

Great project, there's only one thing I'm missing so far: an option to avoid unwanted audio re-encoding.
I mean, I have many family memories where video is huge due to old codecs (e.g. mpeg2 or mjpg), but the audio is already compressed (e.g. mp3) and re-encoding doesn't bring any real advantage (in terms of space), but just some more artifacts.
So, the ability to create a profile where I could set audio to be just copied as it is, would be great.
Even better would be the ability to either set it to always ignore audio re-encoding, or to re-encode just if the source audio is uncompressed (but that would be an extra!).
Thanks for this project!