Hello wanted to report a problem where an audio component was causing crashes when trying to play a sequencer that without an actual audio asset to play. It was trying to get the duration of an audio component that wasnt valid(probably adding a valid check would fix this). I honestly dont know how to submit that fix to the source code of UE4 so at least I could report it to somebody who is able to.
The line that this happens: MovieSceneAudioTemplate.cpp:349