Regarding those, though probably just the last one for I haven't noticed the first:The engine sounds when driving are not synchronized with the action
quote: "Acceleration sounds are delayed and tend to continue long after I'm off the throttle (revving). They don't ever really match up with the action."
solution: Having a web browser (after watching at least a second of a youtube video) or video player (such as VLC or MPC) open while playing the game resolved this for 3 people. I don't think they actively have to be playing anything while you play the game.
Audio desynchronizes or skips/skipping
quote: "I'm fine on the hardware requirements, but the audio is getting way out of hand, to the point where it's almost unwatchable. I'm hearing what's happening roughly 2-5 seconds before I see it. Any one have any experience with this? " -- thread link
quote: "It's now gotten progressively worse, with characters speaking their dialog over each other, or leaving less then a second between replies. This is rapidly becoming unplayable." -- thread link
solution: Unknown, but go ahead and give the workaround for the one above a try.
Seeing how my CPU is kinda sucky, I've been using an FSB O/C to make the game run quite a bit better; downside I've experienced is that cutscene audio is desynced (and iirc too fast + higher pitched), which made me turn on subtitles.. I need to be able to hear/read the end of sentences as well.
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Personally, I'd rather have smooth gameplay and crappy vids than reversed.
Just throwing this out there in case someone else might be stumped by the cutscenes and running an O/C (though mine is a software fsb o/c, so pretty niche I'd guess).