I'm always willing to help people out in this area, FluXulF asked for help, and the other thread is getting off-topic, so here is where I will offer help and answer questions regarding audio and video encoding. If there is enough demand (and I have the time), I will make another thread with tons of general information on the subject, but here, I'll just answer questions.
i primarly use VLC and Handbrake. so those are the extent of my possible support. i have some linux experience but no CLI.