Why can't I sync my audio recording with my video?! >_<

Hi. I’m trying to make Let’s plays (video game commentaries) for youtube but it’s going horrendous. The sound of my voice recordings never stay in sync with the video footage that I capture from the games. (I use a Pinnacle Systems Dazzle, Video Creator Platinum HD to record the games and a Logitech headset for my voice. I learned how to prevent dropped frames in Pinnacle Studio so that’s not the problem.) I one day realized that I had the audio sample rate of audacity set to 44,100 Hz while the videos are at 48Hz which may be the problem. Perhaps if I changed audacity’s sample rate to 48Hz that would fix future problems. However, I made a bad assumption that the recordings would match up and so now I have 20+ audio and video recordings that don’t match but I don’t want to lose. (You can only get blind reactions once you know) I tried changing the audio sample rate of the finished recordings to 48Hz but discovered that this made everything sound funny and high pitched. What can I do? Is there any hope for me?!

I apologize if this is a newbie question but I’m struggling with this and very frustrated to the point of hopelessness. :cry: I want to make good LPs like everyone else on youtube but I’m so confused. Thank you for your help.

Using Windows 7
Audacity 2.0.5
I believe I did obtain the .exe installer

Having a different sample rate shouldn’t be an issue. Your video editor should automatically resample without messing-up the pitch and without changing the timing. In Audacity, you’ll see Project Rate (Hz) in the lower-left corner of the Window. You can change it before saving (exporting) and your audio will be re-sampled without changing the pitch or timing.

How far off is it? i.e. 48/44.1 is about 1.09, so you’d be off by about 1 second after 10 seconds, or about 1 minute after 10 minutes.

If your audio drifts a little (a few percent) it could be your soundcard. The clock in a soundcard is never perfect (no clock is perfect) but some consumer soundcards can be off by quite a bit. But if this is the problem, it should take several minutes before you notice the time-drift.

(I use a Pinnacle Systems Dazzle, Video Creator Platinum HD to record the games and a Logitech headset for my voice.

There might be a “multitasking problem” caused by running a game, a video capture program, and recording with Audacity all at the same time. You may have a multi-processor CPU, but you’ve only got one data bus (and probably one hard drive)… The audio & video data are flowing-in at a continuous constant-rate. They go into a buffer (temporary storage) and are then sent to the hard drive in a quick burst whenever the operating system gets around to it… If the audio or video buffer isn’t read in time, you get buffer overflow, a glitch (gap) that causes messed-up timing.

The usual advice is “don’t multitask” while recording audio or video". (Although there are special game-capture applications, obviously designed for capturing while playing a game.)

Most video systems can slosh back and forth between 44.1 and 48 with no problems. It’s insanely popular to do that. You would get everyone’s attention in a bad way if you made a program that didn’t understand that.

In the horse and buggy era of video we had to deal with the difference between NTSC (US) video and systems that used straight, plain frame rates. The difference between 30 frames per second and 29.9760976… Record in one and you would be out of sync in the other — about 1/30 second per minute. Does that sound like your error?

Much more likely is the computer that recorded your voice and the one that recorded the game were sloppy. You can solve this in the show recording with Audacity Effect > Change Speed. I think the latest version will allow you to change things in very tiny steps so as to be almost imperceptible.

Record a relatively long session as a test and record the game sound with your headset microphone. Play them both later and find out the difference. "The game got to the explosion in 5:16:12 frames, but the audio track didn’t get there until… some number.

If it is sloppy computers (highly likely) there’s no good, easy way to cure it during the recording. The grownups either use insanely accurate separate recorders (Movies) or sync cables between the devices (Studios).

Koz