Why would youtube-dl start running so slow all of a sudden?

[frrobert2]

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Question

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I use youtube-dl on a daily basis and yesterday it starting running very slow.

To do a sudo youtube-dl -U takes over two minutes. I was already running 2020.06.16.1

To do a youtube-dl -g -f best 'https://www.youtube.com/watch?v=S4eH-bak6sg' takes 6 minutes 30 seconds. Time is the same no matter the video url.

I checked my internet speed it is normal. Before this started I had not made any changes to my system.

Since the issue started. I have done the following to see if it corrected it. I updated all my packages. I removed youtube-dl and reinstalled it.
I did the standard reboot
Still slow
I am running Ubuntu 20.04.
I am not a programmer but I am assuming something must be messed up with python or some other dependency. The other programs on my system that use python seem to be running fine.

Any ideas where to look next? I am assuming it is something on my machine

Thank you.

[frrobert2]

The flag. --force-ipv4 solves the issue.
Suggested by arun54321