Youtube-dl not seeing all streams?

[nick1977]

Hi all

I have a file I am trying to download from NBC site.
I only want the audio, so not fussed about the picture quality.
I've used -F to get a list of the files, and got this:

format code  extension  resolution note
hls-63       mp4        audio only   63k , mp4a.40.2
hls-145      mp4        240x136     145k , avc1.66.30, mp4a.40.2
hls-263      mp4        400x224     263k , avc1.66.30, mp4a.40.2
hls-353      mp4        400x224     353k , avc1.66.30, mp4a.40.2
hls-418      mp4        400x224     418k , avc1.66.30, mp4a.40.2
hls-607      mp4        400x224     607k , avc1.77.30, mp4a.40.2
hls-807      mp4        640x360     807k , avc1.77.30, mp4a.40.2
hls-1006     mp4        640x360    1006k , avc1.77.30, mp4a.40.2
hls-1405     mp4        896x504    1405k , avc1.64001f, mp4a.40.2
hls-1803     mp4        1280x720   1803k , avc1.64001f, mp4a.40.2 (best)
[download] Finished downloading playlist: K.I.T.T.Nap

All of them appear to have the same audio as the "audio only" file. I have dl'd that, and the "(best)" one and confirmed they are pretty much identical.

However, if I watch the video streaming on the website, the audio is noticeably better. The download sounds incredibly compressed, and although reported as 44.1khz, sounds a much lower sample rate.

Are there any techniques I can use to obtain the higher quality audio?

Thanks

[nick1977]

OK, so I've found by dl'ing the file hls-1006 that it has a higher quality audio (I think matching the NBC site).
So my question now is, how can I tell which stream has the highest audio quality?

Thanks