issue with animations contains text .. throws warnings and list index out of range.

using windows 10, latest miktex with all packages, running on python 3.8.6 -not 3.9.0 because scipy doesn't support it yet-, lastest SoX, latest FFmpeg version.

I installed everything important and having no problem running examples with no texts such as (SquareToCircle), but i get warnings and exceptions when running (WriteStuff) or any other text-containing animation:


I tried everything, reinstalled everything.. added all important paths(SoX,MikTeX,FFmpeg), edited some parts of (tex_mobject.py) and didn't work so stepped back,i did everything and nothing worked, what could be the reason of the issue..?