DSP latency isnt directly related to sample rate or buffer size, its also to do with hardware and drivers. i dont know about this buffer variable, never had a sound card that had it.
i recommend you look up what the default value for this is on other computers and set it to that, if youre having issues with sound in csgo. also make sure to set the audio delay variable in cs, snd_mixahead, to at least 0.01 (10ms) to prevent audio distortion
ever since MS changed the audio stack with windows vista low latency 3d audio has been pretty much fucked and now it relies on game studios to implement it