For over a year now we have had to replace the Fmodex.dll file by copy/paste from another Diablo game to stop the lag/freeze issue. This is a fatal bug on Hardcore and it also costs the loss of progress in Normal when the freeze occurs during Bounties or Rifts.
Perhaps prior to releasing a new game update the coders could just paste the Fmodex.dll file from another game into the update? I realize some issues take time to resolve but a year is pretty unacceptable when such and easy work around could be performed prior to update release.