We had a problem with some people not being able to hear the sound on Flash videos, even after adjusting all their volume controls carefully. It turns out that sometimes the correct settings don’t get written to the registry when the flash player is installed.

Thanks to “512jones” in the Adobe forums, we have the following fix:

“I just reinstalled my system with XP SP2 and found that sound in Macromedia Flash player (version 9) wasn’t working. I compared it to another machine and found out that – for some obscure reason – the wavemapper mapping was missing.

I tried reinstalling other versions of the Flash player, but to no success … So I added the mapping myself via the registry.

Go to the following sweetspot in your registry:

My ComputerHKEY_LOCAL_MACHINESOFTWARE Microsoft Windows NTCurrentVersionDrivers32

Create a new String value named “wavemapper”. As value give it “msacm32.drv”.

And that’s it, no restart necessary, all your Flash embedded videos will have sound again :)”