@Mozzerfan
I do not doubt that you are right.
I tried the following with aiostreams youtube script
youtube.py -u "
https://youtube.com/watch?v=ZcVdGJO6mcE"And the video has the following resolutions
ID Height VCodec ACodec
----------------------------------------------------
18 360p avc1.42001E mp4a.40.2
140 mp4a.40.2
140 mp4a.40.2
160 144p avc1.4d400c
134 360p avc1.4d401e
243 360p vp9
136 720p avc1.4d401f
The one with ID 18 is the one that plays both video and audio. If I am not wrong, the stream that is used to play the video is a HLS one, but I might be completely wrong or we are talking about different IDs.
Please, let me know if you are talking about the same resolution ID