cannot decrypt some video

[analizer2010]

hello,
some video such as https://www.youtube.com/watch?v=DTjdcgSXMwQ
when I repeat call, sometime cannot decrypt signature( use latest code),
**** decryption code****
var uv={lL:function(a){a.reverse()},NB:function(a,b){var c=a[0];a[0]=a[b%a.length];a[b%a.length]=c},nu:function(a,b){a.splice(0,b)}};var vv=function(a){a=a.split("");uv.NB(a,70);uv.NB(a,67);uv.NB(a,2);uv.NB(a,19);uv.lL(a,6);uv.NB(a,45);uv.NB(a,56);uv.nu(a,3);uv.lL(a,49);return a.join("")};function decrypt(a){return vv(a);}

this info, can decrypt
{itag=18, s=3B603054D4A80E0356E04F7D4E5EF5C396A271FE.6C50B059F5A51CCEA1A168CB473287E54BC1C82E821, quality=medium, type=video/mp4; codecs="avc1.42001E, mp4a.40.2", sp=signature, url=XXXX

this info, cannot decrypt
{itag=18, s=TL5xI2wwRQIhANJE_8nAuKPeSKt26hPGlE5TFmBCId8-7dU4hO=o8gkDAiBQXHjXWMXgELnNT17VH_fCgKF3pYpuPIbpU10SBUybvQ==Q=3, quality=medium, type=video/mp4; codecs="avc1.42001E, mp4a.40.2", sp=sig, url=XXXX

****now i fixed it with
#155 (comment)