I also wanted to explain my setup because on IRC people were telling me to switch the mic to VAC and I would be fine, when that is pointless for my setup.
I run a fairly popular youtube channel (almost 30000 subs, not huge, but not bad). So I do a lot of youtube videos.
When I record gameplay I use dxtory and have it setup like this.
dxtory records using lagarith codec to an avi with 3 audio tracks embedded into it. This is how dxtory records the audio.
audio track 1 is VAC #1 device (this is my default system audio output, so my game audio) vac redirects this to my headset
audio track 2 is VAC #2 device (this is the output channel for mumble) vac redirects this to my headset
audio track 3 is my microphone directly (NO vac device).
With this setup when I record videos for my channel I have a multitrack audio avi with my game audio on one track, my friends from the channel on the second, and my voice on the third. So when I edit I can mute any of the tracks, or adjust volume individually. Comes in handy.
Now when I livestream for our twitch page I use to only do one thing. I would change mumble to output to vac #1 instead of #2. That way OBS would pickup the game audio and my friends from the default vac audio device, and my microphone directly. This worked great up until the latest version.
Now I know the suggestion of using vac for the microphone seemed like an obvious answer to people it really doesn't make any sense. The only reason to use VAC for your microphone is if you are piping audio along with your microphone out as you stream or record. I don't do this.
If I did use the mic on VAC I would still have to disable the default output audio device from the VAC device. Which then breaks my dxtory settings. If I take VAC away as the default audio device, there would be no need for VAC devices at all.
I would think the smarter thing to do would be to not put the mic on a vac port, but to just switch the default audio output device back to my headset directly, and stream with OBS. Then when I need to record for the youtube channel, switch the default device back to VAC 1 so dxtory works again. The only negative to this is I see myself forgetting to do this switch back and then recording with dxtory and forgetting that I didn't make the default device back to VAC 1, and dxtory would record audio track 1 from a silent vac 1 device.
I could also stick with obs .461 as it had no problem streaming (for me) for 2-3 hours of game play and stayed in sync.
So I am curious if you guys have any thoughts on my particular quandary.
I also want to stress that I love OBS and all that Jim does. I fully understand that my needs of OBS are probably way out in left field, and I fully understand if OBS will never work with VAC devices.
I did send an email to the VAC author telling him of Jims finding on his timestamps being messed up. Maybe he will straighten things out on his end! (doubtful, but who knows)