> Might have been an incorrect content-type header?

Thought that as well, and it seems like there are multiple type headers for ogg. But none worked :/ Also not those that worked on other sites, so I thought about Content-Length and errors in my logic when to transcode. Went nowhere.

> I'm looking into https://github.com/audiocogs to add AAC/other codecs to browsers with no support

If you can install that clientside, that is a great feature. I tried to transcode and stream stuff on the server using ffmpeg, and the big problem was content-length – when streaming I could only estimate the correct setting, leading to some songs being ended too soon. Could've changed by now ofc in the new browser version.