The video output looks choppy
Choppy video usually indicates a low framerate. However, low frame rates may have different root causes. Here is a step-by-step guide to isolate the cause of a slowdown:
- Check if Videosync requires too many resources.
- Watch the FPS indicator in the Control window. If it is significantly lower than 60 fps, Videosync is not running as fast as it could. The cause is usually that your computer is unable to perform the necessary video operations in time, either decoding the videos you are playing or rendering instruments and applying effects take too much resources.
- If you are using video effects in your set, try disabling effects one by one to see if disabling one or a number of them restores the frame rate to 60fps.
- If you are playing video files with a high resolution or data rate, try playing a smaller video and see if that returns the frame rate to normal.
- Make sure your system settings are optimal for real-time video performances, see System settings
- Check if your computer hardware is suited for what you are asking it to do. For more info, see Hardware tips
- Check if other applications occupy your hardware capacity.
- Open the macOS Activity Monitor, select the CPU tab. If an application other than Videosync is using a lot of CPU (30% or more), the slowdown might be caused by this other application. If you can, quit the application.
- A common scenario is that your audio effects in Ableton Live use a lot of CPU power and don’t leave enough room for Videosync. In this case, you may need to get a different computer to run both video and audio, or get a separate computer only for video (see Networked Playback)
- Make sure the frame rate of the video files you are playing is high. Try playing your videos in another application like Quicktime, without Ableton Live or Videosync running. If the video is still choppy, chances are the source video frame rate is not high enough. There is no way to decrease the sloppyness apart from obtaining a different rendering of the video if available. For tips about re-rendering video and using video codecs, have a look at Encoding video.
- If you are working with a laptop, make sure it has enough battery. The battery can slowly drain even if your power cable is connected. Real-time video processing can put a constant excessive strain on CPU and GPU, which in some cases requires slightly more power than your adapter may be able to provide. If the battery is drained, the performance of your laptop will drastically decrease. We had performances where we had to make sure not to leave Live and Videosync running long before the start of the performance.
- You can always get in touch via our forum and share your hardware, setup and which steps you tried to go through.
When I start a silent video clip, I hear a buzz
Videosync never generates audio, so the sound you hear should come from something else.
Here are some things to check:
- Are you sure there is no audio in the video? To entirely mute the audio of a clip, you can turn the clip’s gain fader all the way down. See this article in Live’s manual for help.
- Do you hear the electrical buzzing when playing the video in another application like QuickTime (without Live and Videosync running)? If so, you know that Videosync has no additional influence.
- Do you have a crosstalk or grounding issue?
- Does the buzzing stop when disconnecting the projector/screen? If so, you may have a crosstalk issue.
- Does touching the computer make any difference? If so, you may have a grounding issue.
- When you’re on a laptop, does disconnecting it from power have an effect on the buzzing?
Issues like these can usually be solved by using an external sound card instead of the computer’s built-in output, using a DI box, or changing to an electric power group that is separate from other equipment.