DSOAL doesn't seem to make a difference with 3D Sound and EAX turned on in the game's menu. There doesn't seem to be reverb or echoes or anything in environments which would make sense to have them. I installed the 32 bit version of OpenAL, took the dll from the System32 folder, put it in the 32 bit directory of the game, along with the DSOAL dll.
I also tried using both dlls from release r10112, instead of using the one installed on my machine, and I also notice no difference.
Am I doing something wrong?