Adding Audio in Video in AE 2020

Bad news for you: No magic buttons. You need to work up an understanding of how AE's rendering actually works, what the various output modules andrender settings do and so on. There simply is no way to do a pass-through rendering and "just add audio". and as you already found out, AE is not great at audio processing to begin with, which is of course natural on some level, as any audio more or less is merely meant as a reference track or a trigger for audio-driven effects. that said, we can't advise specifically without knowing any details about your project, your render settings and so on. You might want to start by actually reading the relevant sections of the online help instead of just dumping your work on the render queue and using default settings. finding a good tutorial also might not hurt. And the usual basics also apply: Convert compressed audio to WAV/ AIFF, match sample rates and settings everywhere, pick a sufficient data rate for outputs. the rest is simply a matter of learning and accumulating experience.

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