I have requested to upstream this patch to the original openal code:
https://svn.thedarkmod.com/publicsvn/darkmod_src/trunk/ThirdParty/custom/openal/patches/1.21.1/mxcsr.patch
Here:
https://github.com/kcat/openal-soft/issues/926
They have proposed commit, but I have not enough knowledge about the patch to comment of it. If someone could go there and give it the "okay" it would be very appreciated.