Most formula-to-speech software only works with MathML, so you would first need to convert the LaTeX you find on arXiv.
There may be an alternative, under development for AWSunder development for AWS:
Tex2Speech takes LaTeX documents and converts them into spoken audio.
Here is the documentation, and this is how it sounds when confronted with a simple equation.
It looks promising, but I read that you need an account with AWS, which may well complicate things.