Thanks TGS, I'll have to try some of those things when I get the chance. Not sure what a PAI is, but I can find that out. The odd thing is the new track starts out in synch but goes off more and more as the two tracks are played together. the longer the tracks, the more out of whack the newest track becomes.

Thank you!

TGS
The control button drag is a good trick to know, I can fix it pretty good that way. I'm still baffled though. The original track and the subsequent ones (or add ons, although all of them are add ons) are all recorded the same way.

So, if anyone out there has a suggestion I'd still like to hear what is going on that I need to drag and shorten new audio tracks to get them to synch with the original. It just shouldn't need to be done.

I'm glad the Ctrl / drag has helped
I was wondering about interfaces because I sometimes use a FireWire mixer to record up to 14 tracks at a time, but somehow the timing on this drifts slightly with all my other ways of recording (camera or audio line in) It's not much of a drift, and if I hadn't been trying to line up video with it, I probably wouldn't have noticed anything wrong. Ctrl & drag is my only way of solving that as it's apparently an internal timing problem of the FireWire mixer.
So, if I add on using the FireWire mixer, then I'm playing against a slightly off time recording and the new track would be even worse when done. I had to Squish my video to a pitch change of -0.00358 to match the audio recorded (1 hour recording). This means my FireWire audio is slightly fast after recording. If I add on using the FireWire mixer, than I should be technically slightly out of tune and will play slightly faster on the overdub. The overdub would be twice as bad as the original. The only way I can fix is to Ctrl & drag the add on tracks. (-0.00358 is a very subtle change and hearing the pitch difference would be tough.) So I'd be scratching my head after overdubs too if I hadn't tried lining up video from the beginning of using this FireWire mixer.
You could also try the search here, as I've seen the question asked a few times over the last few years
Possibly check to see if some New drivers are available for your sound card. Or if you changed them recently.
Wouldn't be surprised if some Windows update messed something up.
Even though I do make some CDs and I'm primarily a musician, I usually work with 48Khz because I'm also working with video a lot too. My audio project properties are set to 48,000 (sample rate) 16 bit depth (I would use 24, but I have trouble with some plug ins if I do) and resample and stretch quality set to 'Best'
My Ruler is set to 'Time & Frames' with 120,000 beats per minute, 4 beats per measure, Notes that get one beat "Quarter"
If I need to make a CD from 48Khz, well good ol' Vegas will convert it to 44.1 as soon as you burn a CD
One other thing I can think of is latency, but you'd only have to slide the new track over a few milliseconds to line it back up. You say the new recording starts late and gets worse. Latency usually makes the new recording start late, but to get worse is why I thought you may be recording, for example, using a USB mixer set at 44.1 and Vegas set to 48Khz (or vice versa) Check your Vegas Preferences in Audio Device tab, be sure "Automatically detect and offset for hardware recording latency" is checked and the right audio device is checked
I don't know if a sound card can go hay wire, but who knows. If the internal timing of it's crystal has somehow changed, maybe what's recorded is slightly off and when you add tracks it compounds the problem. (that's what my FW mixer does)

Oh yeah, PIA = Pain in the A$$

I doubt you'll see this, kingbobo, but I was just trying to make some new overdubs, using my regular audio card inputs, against some previously recorded drum tracks made using a FireWire Mixer and they go out of sync almost immediately on playback
I don't get why this is happening either. Ironically, I also made some video while making the drum parts, and it stays sync'd with the Drum audio, even though I added the video to it afterwards. It's only the new audio stuff that goes out of sync right away.
I'm not sure what the cause of your problem is, but it seems like whenever I add something to my FireWire recordings, it goes out of sync. I don't know if something is somehow imbedded in the recording, I've never heard of such a thing. But this makes no sense to me.
When I was mentioning it in the post above, those video recordings were an hour long and they barely went out of sync.
My new FireWire recordings are only 2 to 4 minutes each, and the newly added sound card audio goes out immediately, although maybe the video would too, if it was 20 minutes long or longer.
This is what makes no sense. My sound card audio has almost always stayed in sync with video recordings in the past, so why the video is matching the FireWire and yet the new sound card audio goes out right away, is beyond me.
I've made sure my FireWire mixer was off and I rebooted to make sure I was back to normal computer configurations.

I'll hazard a guess at what is happening here.

You have recorded audio from two different audio sources (your firewire mixer and your audio card) but you have not made sure they are both being driven by the same master clock source. Because of this, the sample rates they are recorded at will not both be exactly equal - one may be a touch below 48kHz while the other is a touch more than 48kHz for example. When you play them back you play them back at the sample rate of the device you are playing them back through. This will be correct for one of them, but slightly wrong for the other one causing it to drift out of sync.

It is important when using audio from different sources (even if they are recorded at different times) that they are recorded using clocks that are sufficiently in agreement (ideally, both synchronized to a single master clock) otherwise this kind of sync problem will occur. How bad it is depends on how great is the disparity between the clocks used in the recordings. If you are lucky it may be so small that you do not notice any appreciable drift even over a long period. But with some kit that is not intended for serious audio use the nominal clock rate may not be terribly accurate and in these cases unless steps are taken to ensure that these devices are set to use an external clock that agrees with the clock used to record the other audio there will be sync problems.

Mark

I sort of knew about the internal timing maybe being off. What is throwing me, is that the sound card always matched my video in the past. On my original recordings using the FireWire mixer, my video would slightly drift, over an hour period with the FW recording, with the FW recording being slightly shorter than the video.
The difference between then & now is I put some new drivers in my FW mixer and maybe that changed something, but I still need to test against a longer video. I was matching 2 to 4 minute video pieces against the FW recordings and they may be too short to drift out of sync, since it was a very subtle drift on hour long recordings in the past.
Why the soundcard goes out immediately with both, when adding is what makes no sense. I can hear it start slipping within a few seconds on playback, yet I was just playing against this recording
The sound card still seems to stay in sync with video recordings when done without the FW recordings, even though I record & add that audio afterwards. All the properties still say 48Khz, 16 bit
The video is not drifting with the FW in the 2 to 4 minute range
Well, my Phonic Helix is a cheapo alternative, but I must say it does make some nice quiet recordings. I see no VU meter activity if no sound is being made. (that's usually almost 2/3's full of noise with the sound card used as a recording source) It's the company Phonic, I'm not too crazy about. I haven't been able to achieve contact with them yet.
I like that it's taken months for me to finally hear I may need to sync the timing of everything to an external source. Now I'm going to have fun figuring that one out.

Here's another funny thing, I also tried re-rendering a wave from the multi-track FW recording and play along with that, using the soundcard and it still goes out of sync.
So, FW and Video seem to stay in sync
Video and Sound card add ons, stay in sync (as long as no FW stuff is around)
But FW and sound card add ons, go out immediately. (with or without video)

When I re-rendered a new wave from the multi-track FW recording and made a new soundcard recording, that still went out of sync, that's when I started wondering about something being embedded in the recording. This timing thing you're talking about, seems to be embedded
It's a very noticeable difference from what I'm used to

Thanks for the external timing tip. At least I have a clue now.

Edit: I just did a one hour recording with Video. The video ends up being about 1 second shorter than the 8 channel FW recording after lining up on the timeline.

Alright folks, it's been a while, but thank you for the input. Could you explain recording audio from two different sources? It seems most of the responders know more than I do about this stuff, but I don't think I'm using two different audio sources when recording. Here is what happens; I record using a mic into the computer with a metronome counting out loud to the click. Then I record (again count out loud) another track the same way along to the first one, and when I play both tracks back, there is a discrepancy by the time I count to 30 or so. Not only is it out of sync, but the length of time in playback is longer than the first track although they were originally counted off in time. The pitch seems fine. Also could you please explain what and how do I adjust “master clock source”?
Thank you.

kingbobo:

Please fill out your system specs in your profile.

What audio hardware are you using?

What driver model are you using? ASIO, Wave Classic, Mapper?

What is the buffer size you have set up to use in Vegas?

Peter

Peter. I'm not sure how to repond to the things you mentioned. how do I get to my system profile? I don' t know what the other things are, or how I can find out what I'm using. Mapper sounds familiar, but I don't know the rest. Any suggestions would be greatly appreciated.

Thanks

Peter. The buffer size is set to 0.35. I am using Wave mapper.
Thank you.

Please fill out your system specs in your profile.

Change your forum settings by selecting the "Forum Settings" link above.

Fill out your system specs and show them.

What audio hardware are you using?

What manufacture of audio hardware are you using? Did you install a second audio device in your machine or are you using what is built into your PC?

What driver model are you using? ASIO, Wave Classic, Mapper?

Mapper, Wave Classic, and ASIO are types of drivers for audio hardware. From Vegas' preference page for Audio Device you can select what to you.

When recording in Vegas, you should use ASIO drivers if at all possible.

What is the buffer size you have set up to use in Vegas?

The buffer size determines how much latency is being used to stream audio into and out of the PC.

You should spend some time with the Vegas user manual and the on line help. You should also look through some of our white papers and FAQs. There is a lot of information in these documents that will help you get an understanding of how Vegas works with regard to audio hardware and drivers.


Peter

You should use ASIO if possible.

If not, then you can adjust the recording buffer latencies from the Audio Device preference page.

Again, this is covered in the manual and on-line help.

Let me know if you have any more questions.

Peter

Thanks a lot Peter, I'll check out those options before I start asking more questions. (I do go through the online Vegas help, and I have a couple of books written by others, but this has had me stumped for a while). But one more thing -this may sound odd, could you tell me what is meant by hardware?

Thank you

...could you tell me what is meant by hardware?

Hardware is your PC and what is intalled in it. This is in contrast to software, which is what Vegas is.

Audio hardware is the physical device that produces audio on your computure. There are on - board audio devices that all PC's contain. You can also purchase higher end audio hardware to improve peformance and provide additional input and output options.

Peter

Peter
After reading all the links I could find, I realized I could download a free version for ASIO software. That seems to work! I also listed my profile info. If there is something else I should consider that hasn't already been discussed, I'd be greatful to hear more on the topic. I still don't know why the editing program has has worked fine until recently. But thanks again for your help.

Hi guys! I'm new to this forum. I also have audio/video sync problems.

I set up my HD Cam (Canon HF11) and my Zoom H4 (portable audio recorder) and record a drum performance. Later I want to use the audio from the zoom and the video from the DV cam i.e. not using the ausio of the video. Right, I use Sony Vegas Pro 8b. When I line up the audio from the DV Cam with the audio from the Zoom, at first they play in sync but start to drift with time. I can even see that the audio from the Zoom (that was edited and rendered in Cubase) is slightly longer. How is this possible? Something has actually changed reality....I mean if I record exactly 4 minutes of audio and video, surely that should be a fixed value?

Cheers
Peter

See the explanation I gave a few messages ago in this very thread.

Mark

Ah, thanks Mark. So what you are saying is that a bad clock can make something that happened in 4 minutes...now play out in 4 minutes and a bit? i.e. change the reality slightly? But wouldn't that imply a slight pitch shift?

I'm really not a techie person and am still baffled by this...

Is there a way to get my zoom and my cam to play by the same clock?

Cheers
Peter

If you record your audio on a device with a clock which is nominally running at 48kHz but is actually running at 48001 Hz, and then play it back on a different device, this time with a clock which is nominally running at 48kHz but is in fact running at 47999 Hz you will indeed get a pitch shift. The shift will be a factor of 2/48000 = 0.00004167 approx. This equates to 0.072 of a cent (where a cent is one hundredth of a semitone). This is far too small a pitch change for anyone to notice under normal circumstances.

But over a longish period of time, your 4 minutes, say, the time disparity in this example will equate to 2x240=480 samples. 480 samples at 48kHz is 10 milliseconds and a difference of 10ms is very noticeable when compared to another audio track playing back at the correct speed, particularly when drums are involved - they will start off in sync but gradually drift out until by the end of the 4 minutes each drum beat will sound like a flam.

Most pro audio gear can be driven by a master audio clock to ensure that this does not happen. But it is not usually possible to do this with the kind of cameras that most of us can afford, or with devices like the H4. If you are unlucky and find that the nominal 48kHz audio clocks in your recording equipment disagree to a noticeable extent then you will probably have to fix the problem another way.

Fortunately Vegas makes this pretty simple. Make sure that the two tracks are in sync at the beginning, and then use the audio stretch facilities to shorten or lengthen one of the audio tracks until the ends match up exactly. You should then find that the tracks are in sync all the way through.

Mark