Google Voice's web site is not down.
By "constantly times out", do you mean that the page starts to load, but then sits there, usually with a circular "spinner" icon?
If that's the case, the cause is on your computer. Some piece of software, such as uBlock Origin or Malwarebytes is blocking something required by Google Voice, or, you have a specific extension that is blocking it.
Do not block WebRTC or javascript. Do not block any [*.]google.com cookies. At least temporarily, disable all browser extensions and cookie blockers, clear the browser's cache, history and cookies, close and reopen the browser, and try again.