Crc32 error is a file checking process. It somehow comes up with a code of letters and numbers that is extremely specific for a certain file. It's extremely useful for checking whether a file was downloaded correctly or for patching programs. Say your file has a certain crc32 code that corresponds to being unpatched, the patching program will then patch it. But if the file has a code that corresponds to being patched, then it won't. Also, most anime sub teams throw this on the end of the anime episode names in brackets and you can self check it yourself just in case there's something wrong.
For example, here's the latest episode of Clannad from Eclipse:
[SS-Eclipse] Clannad After Story - 22 (h264) [537CAA82].mkv
537CAA82 is the CRC32. A program called Hashtab can easily check that. More info on that from
Wikipedia.
As for your sound issue: I would probably blame the game. I remember back in the day when ff8 was working on my computer that some sounds were missing as well when I compared it to the playstation version. It was mostly the bassy sounds. For example when you summoned diablo it sounded horrible on the computer. Then again, I have since built a better computer with an actual soundcard and got me better 2-channel speakers that have a subwoofer and that may have done the trick.
Whats your soundcard and speaker system?