this is very strange. It seems to not be loading properly, the text immediately starts when the scene finishes loading. What browser do you use? I've yet to see this error. The downloaded version will likely work if you want to try that, web builds can be unstable.
After thinking a bit I actually think the scene is loaded properly, but objects are drawing in the wrong order. The beeping you hear is the text sound which would imply the text is working, but I think it's appearing behind the rest of the scene. No idea what would cause that. If you keep pressing Z I think it should progress through all of the dialogue and let you play, but you'll miss a lot of important information..