Mouse click on the transport bar.

Do you notice this behavior in other projects or just this one? Opening in V15, then saving a new project file might possibly help? I haven't seen this kind of behavior before, maybe someone else here can give some suggestions as to what is causing it.

All this sounds very similar to what I get from time to time. And my “cure” is to go into Prefs and momentarily switch Audio device. I have absolutely NO idea why this works, but it does. It has to be something going on locally with my system, but I just wanted to share.

I have only opened this project in VP16 as it was one I was currently working on. It worked OK for around 30 minutes and then, after adding a vignette (vegas plugin) fx to a couple of clips it started with this behaviour when I tried to play the project.

My audio device is a UAD Apollo. This appears to be working OK using the ASIO audio driver. I have noticed a lot of audio glitches on playback in this version after adding any sort of processing on any video clip. Buffer size is set to 256 samples at 48K which should be fine. Processor load rarely goes above 35% total (4 cores i7) during playback.

Also, since after the original install Vegas had many crashes trying to scan the copious number of VST's used in the audio processing suite (Cubase 9.5 here), which has always been the case with new VP installs, I have disabled the VST's that are read from the Steinberg folder, leaving just the VP VST audio plugins. I was hoping that there would be a way to configure this before the ran its vst scanner so as to avoid this chicken-and-egg scenario.

I'll try disabling the audio driver and see if that fixes it.

Some more findings after investigation...

Changing audio driver made no difference.

Muting all Video tracks made no difference.

Moving the audio track to be the second (instead of first) track made no difference.

The video starts playing at around frame 900 when the 'Play from start' is clicked. The audio plays from the start. What I see is the playback cursor jump to frame 900 (or so) and start playing there, with the audio track playing as if it was playing from frame 0. Each time I hit 'Play from start' the starting video frame increments further.

It definitely looks like a bug in VP16 from here. Some of the video was aligned using slip mode in the video track for an event (to sync with audio events). Not sure if this helps with the bug.

Just noticed also that hitting play-pause-play skips the video ahead by around 2000 frames each time.

VP16 is pretty much unusable at the moment.

Right! It’s rollup yer sleeves time. Unplug ALL USB devices. Switch off PC. Turn on PC and start reactivating/replugging in your devices, one-by-one. IMHO, there is definitely some communications issue going on with your external devices. Maybe this isn’t the issue but you’d have knocked it out of the equation.

Very, very frustrating indeed.

Pulled the USB devices, restarted. Makes no difference.

I think VP16 at some stage rooted this project due to some obscure bug.

Luckily when I saved the VP16 version I did not overwrite the VP15 project.

Pulled in the VP15 project again, which works fine and re-saved as another VP16 project and will try and replicate the edits carefully to see where it falls over again, if it does.

Will report back here if it happens again with whatever detail I can add.

If you can replicate, if you can record a video of it happening using OBS Studio or a similar image capture app, it might help with getting it sorted faster.

Without any additional editing, just reloading the project caused this to happen. Will add a video when I get a chance.

Here's a short vid showing the problem (taken with a handheld iphone).

The VP15 project was opened with VP16, saved to a separate file and then closed. Next day it was opened again and this is what happened (and continues to happen). No editing was done this time, just open and 'save as' to a separate file. No other applications are running. Although I muted the studio monitors when shooting this, the audio starts playing back from the start, and the video playback starts where the cursor jumps to.

Weird. And unfortunately VP16 is not usable here as a result.