That sounds quite...interesting. XD
Mac: ...I don't know. XD
Perhaps try FlashBlock or AdBlock in Firefox?
As for Safari, you're on your own. x)
1. Shut down mozilla/firefox
2. Find “libflashplayer.so” in your plugins directory.*
3. Edit this with a HEX editor**
4. Look for the string “/dev/dsp” and change it to “/xxx/xxx” - now it can’t open the sound device.
6. Restart Browser
(I may even do this later...)
* - This'll depend on where your Mozilla is installed to. I'm unsure where mine is however. o.o
** - I think you'd probably be able to use gedit or kate to edit the file...emphasis on think. I've never edited a .so, so I don't know.
Hope that helps!