I'm using Flash Player 11.6.602.171 in Firefox 19.0.2 with Windows 7 and a 5.1 sound device.
I just noticed that when playing stereo sound in Flash (e.g. Youtube, Soundcloud), Flash is upmixing stereo sound to 5.1 by duplicating sound into the rear speakers and doing some kind of home-made bass management with the LFE channel.
This is obviously completely wrong and is clearly a bug, since stereo is not meant to be reproduced using more than two speakers and Flash is the only software that behaves that way. I don't have this issue with other players (e.g. foobar2000). This is not an isolated issue; indeed, other people seem to have the same problem.
Is there some way to disable this behavior and force Flash to output the stereo sound untouched?
Best Answer
Seeing that Adobe closed the bug as "working as intended" (which is just plain stupid), I decided to fix it myself.
Here's the result: StopBraindeadSurround (open source, WTFPL license)
To install, just copy
audioses.dll
into your Flash player directory (typicallyC:\Windows\SysWOW64\Macromed\Flash
if you're using 64-bit Windows). You might need to copy it again after Flash Player updates.Here's an extract from the README:
Those interested in the implementation will find a description of how it works in the source code (
sbs.cpp
).