WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] 8nTdBaxTf5o: nsig extraction failed: Some formats may be missing
         n = 3SAHOwYV6zEKIt41L ; player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] Falling back to generic n function search
         player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js
WARNING: [youtube] 8nTdBaxTf5o: nsig extraction failed: Some formats may be missing
         n = MRIoHEz9MyiYYLDPG ; player = https://www.youtube.com/s/player/e7567ecf/player_ias.vflset/en_US/base.js