Question / Help Microphone desynch, a constant issue.

[Goati_]

Hello,
I stream with a webcam (microsoft hd live 3000) and a microphone (blue snowball), and have a delay set on both for 600ms so that I can have everything in synch with the game (elgato hd has that sort of delay).
I even tried disabling the microphone under the "audio tab" and, instead, setting the microphone as the audio device for the webcam (under webcam's properties), but with no result.
The issue is the following: when I start the stream, I go through 2 scenes before switching to the 3rd one where my webcam and elgato are captured; what happens everytime is that the webcam and the microphone are not in synch and I have to fix that by quickly restarting obs (which is unfortunately very annoying). I'm assuming there's no desynch after restarting cause I just start from the scene I play on without switching. Although if I switch to a "brb" screen while streaming and then switch back again, there's no desynch issues..
I should also mention that, everytime, the webcam delay also appears to be doubled and I have to reset it and set it back to 600 again.

This has been going on for months without me being able to find a solution, I suspect it may have something to do with my bad pc and switching scenes, please help me, it's way more annoying than it may sound like :D

I'm including my latest log file (from a cast with no desynch issue since I had just restarted to fix it and I can't provide a log with desynch issue since those casts are usually around 15 min and don't get logged), and reading it actually gave me clues, scene switching taking too long so I should have less sources?.. And gotta disable some 'synch audio to video' option?.. Still need help, wouldn't want to mess things up further.

Thank you for your attention.

Log file too long, uploading it through OBS's function
https://gist.github.com/f0a6459e21dd62c0a6dc

 

[FerretBomb]

Well... your logfile shows a few problems, though I'm not sure which one is causing the issue.

1) Low bitrate. 720kbps really isn't enough for 480p@60fps.
2) CPU issues. The i3 is duping, skipping and late on a lot of frames. It's weak. 60fps appears to be too much for it. Set to 30fps (will also fix point 1).
3) Elgato and webcams not set as Global sources. This may be one of the things causing the scene-change desync. Add them to your intro slate and hide them behind the splash image. This will let them initialize and stabilize before they're shown on screen.
4) Aero disabled. Enable it. It speeds up Window and Game Captures greatly under Win7, and provides smoother performance overall.
5) Monitor captures in use. Never use Monitor Captures under Win7. It's terribad and slow thanks to how MS coded access, and can actually cause major performance and sync problems system-wide. If you need to capture your monitor, use a Game Capture of the DWM process. It'll only cap your primary monitor, but it's not horrible like monitor capture is (under 7).

I'd also recommend enabling 'use Mic QPC timestamps' in Settings->Advanced. Set your webcams' mic/audio devices to Disabled, and put your mic back through the mic channel.

The error you're seeing is because Settings->Advanced "Force Desktop Audio to use video timestamps as a base for audio time" is checked. Uncheck that; it's not needed unless you get on-system audio drift (not from a capture device, but a game being played/captured on-system losing audio sync; it's fairly rare).

Elgato should be enabled as a Global source, with Use Buffering enabled and set at 0 or 1 (this helps prevent internal desync with the captured video/audio). Elgato USB 2.0 devices all have around a 2000ms delay inherent.


TL:DR;
-30fps. i3s are economy chips, and video encoding is heavy. Even at 480p.
-Enable Aero
-Stop using monitor captures; they're very, very bad under Win7
-Global sources are your friend

 

[Goati_]

Hey FerretBomb, thanks for the reply.
It was very helpful (and brief, no need for tl:dr; haha).
I am aware my i3 is bad, I'm having a full pc upgrade soon.
I followed all of your sweet instructions.
The 60->30fps downgrade though is kind of bugging me. I stream sega mega drive/genesis (yeah I know, "elgatohd60? wat"), and 30fps often means disappearing sprites (instead of blinking) and generally less smooth (? I don't know myself, been told so by viewers). Is a 60fps setting causing image quality loss or just performance issues? I don't mind slow pc and stuff if that gives better quality.
Sadly, where I'm at now, that's the maximum bitrate I can get without losing frames.

Thank you for your attention, you've already done a lot!