There are no aif files, only AIFF or AIFC (AIFF is a subset of AIFC -
AIFC allows compression on the soundfile).
In the Windows world, file types where recognised with the help of a
file extension, which could be only 3 letters long, so on Windows, an
.aif extension meant that the file was an AIFF or AIFC file.
So, there are probably no difference between aiff and aif, but as you
don't precise what problem you have with buffers, I'm afraid I can't
help much more.