content-type=audio/wav problem with Quicktime in Safari on Mac

[Solarin]

I am having extraordinary difficulty with Safari on Mac playing a WAV file that we generate on-the-fly as part of an audio captcha service.

I set the content type to be audio/wav, the content-disposition header to be "inline; filename=captcha.wav" and the Cache-Control to "no-cache, no-store, must-revalidate, max-age=0".

This is working in all browsers (including safari on windows) except Safari on Mac. I know the Quicktime plug-in on the Mac is working correctly within Safari as I have been able to play a WAV file directly with an HTTP URL.

Perhaps this is a problem with HTTP vs HTTPS? Our captcha service page is in HTTPS.

Obviously this needs to work for a large public audience.

Suggestions?