[nfbcs] Captcha

[Tracy Carcione]

The hospital I work for is creating a system where patients can see their
medical records online, and I volunteered to advise them on accessibility,
so far as I can.  The system is using a captcha during registration.  It
has an audio version, but it's very hard to understand.  It took me 4
tries to solve it, although it might have been easier if I'd had
headphones on.
Is that usual for audio captchas?  Can anyone give a site where captchas
are particularly well-handled?
Thanks.
Tracy