Welcome to the XA forum. Feel free to post!
I think I'm having the same problem with my XA, which I just bought off eBay. I thought maybe it was because i wear glasses and the glasses were making it (and the shutter speed scale) hard to see..
Wish I had an answer for you, but I thought I'd let you know you're not the only one with this problem.
use a tiny piece of black tape or even a sharpie to dot in a black square -- see this website
i just did it on my camera and it worked perfectly! god i love the internet...