I had similar issue but solved it myself searching online. Sometimes, Updating Windows and graphics drivers can solve the issue. I downloaded the missing DLL from this site: https://dlldownloads.com/openal32-dll/. My problem was solved this way replacing this DLL file with the older one from the game's installation folder. I think you would have no problem this way. I am aware that developer has solved this issue. But, if someone has similar one, then they might be benefitted from this.