The XAudio2 doesn't "break" any games, Farcry 4 and Watchdogs are the only games that have problems with REALTEK, because people using "real" cards like sound blaster have no problems with that mod.
From using Creative's "fix" for Watchdogs and Farcry 4 on my Sound Blaster sound card, it seems to be a BS patch, they just push the stereo audio to all channels with it.
From my understanding, and please educate me if you have more information, It is a problem with XAudio2 and DDL, not just realtek (which is why Creative came up with the "fix" that they did).
Quoting the original MSDN post by federken that listed a way to fix it:
"I recently stumbled across this problem again and investigated a little further.
XAudio2 seems to query PKEY_AudioEngine_DeviceFormat to determine the speaker configuration. This is a WAVEFORMATEXTENSIBLE structure. XAudio2 does not check its "SubFormat" field for AC3/Dolby Digital. It always assumes some kind of PCM. And apart from the subformat GUID, a DDLive WAVEFORMATEX looks like stereo (2channel, 48kHz, 16bit - because an AC3 bitstream is compressed and fits into the bandwitdth of stereo PCM)!
A proper solution would to fix the XAudio2 speaker detection, e.g. query the MixFormat with IAudioClient::GetMixFormat, which is 6ch 48kHz 32bit float for DDLive.
A hacky work-around involves patching the XAudio DLLs (XAudio2_*.dll in both \Windows\System32 and \Windows\SysWOW64). I replaced the binary value for the PKEY_AudioEngine_DeviceFormat property key (hex: 4D 06 9F F1 2C 08 27 4E BC 73 68 82 A1 BB 8E 4C 00 00 00 00) in these DLLs with a value for a key from the registry which looked more like 6-channel. In my system with a Realtek HDAudio chip, I chose the registry key "{e4870e26-3cc5-4cd2-ba46-ca0a9a70ed04},0", which might be related to the "OEMFormat". The hex value to replace the value above is accordingly "26 0e 87 e4 c5 3c d2 4c 46 ba ca 0a 9a 70 ed 04 00 00 00 00".
I checked this with the Xaudio2 sample from the DX10 SDK and with a Xaudio2-enabled game. Both give me proper 5.1 surround sound now.
However, I really hope to see this fixed by Microsoft." (
http://xboxforums.create.msdn.com/forums/t/22533.aspx)
I hex edited the dll files myself as he did and confirmed that it fixes the issue for the games on both the onboard realtek audio with the DDL unlocked drivers AND the Sound Blaster X-Fi Surround 5.1 Pro without having to do Creative's bogus work around.
This problem has existed since the change from Windows XP to Vista in 2008 and is NOT only with Watchdogs and Farcry 4, as the problem existed before those games did.
http://answers.microsoft.com/thread/304c4dc9-ea55-48f4-b08b-9946700763fe
http://forums.tweaktown.com/gigabyt...en-vista-windows-7-when-xaudio2-api-used.html
http://forums.seriouszone.com/showthread.php?t=61046