If UT3 crashes with your X-Fi (and maybe audigy) when OpenAL is enabled und runs fine when OpenAL is disabled, then this might be the solution for 5.1 Sound:
Replace the OpenAl32.dll (version 6.14.357.22) from UT3 with the same file (version 2.1.2.0) from Blacksite Area 51. It works for me, couldn't play one minute before, now everything seems fine. Though I haven't checked whether the soundquality is the same, it is 5.1 and sounds ok.
I could post the dll if nobody else will, just tell me how, I've never posted on the internet, silly me.
Replace the OpenAl32.dll (version 6.14.357.22) from UT3 with the same file (version 2.1.2.0) from Blacksite Area 51. It works for me, couldn't play one minute before, now everything seems fine. Though I haven't checked whether the soundquality is the same, it is 5.1 and sounds ok.
I could post the dll if nobody else will, just tell me how, I've never posted on the internet, silly me.

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