Actually, we should be worked be ADA compliant and have worked to make this accessible.

Screen readers should pick up the alternate text.

<a href="javascript:AYAH_fallback()" style="position:absolute;left:-10000px;top:auto;width:1px;height:1px;overflow:hidden;">Please complete this audio captcha before submitting the form</a>

Also, I know the audio sucks, but it's the most secure out there, otherwise it would just be a giant hole for bots to get through. It's one of the things we want to make better.

In fact, we've experimented with audio games and had some good results.