The following guide lists some common things to check when you are experiencing performance issues in vMix.
The graphics card is used for all input and output video processing in vMix.
A modern mid range graphics card such as the Nvidia 1050 Ti or higher is recommended for vMix.
The faster the graphics card, the more inputs you can add and the higher the resolution that can be used for streaming and recording.
Check the Render Time reading at the bottom of the main vMix window. If this is consistently above 20ms, the graphics card is likely at its limit.
1. When using NVIDIA graphics, make sure the latest drivers are installed from www.geforce.com.
2. Uninstall the "GeForce Experience" software included with the driver, as this can significantly reduce performance on some systems.
3. From the NVIDIA Control Panel, go to the Manage 3D settings and set Power Management Mode to "Prefer Maximum Performance"
4. If using a large number of inputs and your graphics card supports 3GB of memory or higher, turn on "High Input Performance Mode" in vMix Settings under the Performance tab.
The CPU is primarily used for audio/video compression and is used by the Recording and Streaming features in vMix.
You can see if CPU is the bottleneck by keeping an eye on the Recording Information window while Recording.
This window can be found by clicking the [i] button next to the Recording Setup and Start buttons at the bottom of the main vMix window.
This will show the number of dropped frames and the likely cause.
1. Streaming: If you have an NVIDIA graphics card installeds, try ticking Use Hardware Encoder tick box in the streaming settings to reduce the use of the CPU:
2. Recording: If you have an NVIDIA graphics card installed and Windows 10, try recording to MP4 with Use Hardware Encoder enabled. This will reduce CPU usage:
The following settings should be checked to ensure vMix can provide the best performance possible.
Settings - Display
Master Frame Rate and Output Size should be set to match the cameras used as closely as possible.
Settings - Performance - Output Format
This should be set to UYVY or YUY2
Settings - Performance - Low Latency Capture
This adds additional load on to the Graphics Card and should be unticked unless low latency is preferred.
Settings - Performance - High Input Performance Mode
This option takes advantage of newer graphics cards with more than 3GB of memory such as the GeForce 1060 and higher.
Enable this option if you are using a large number of inputs and have a newer graphics card.
Settings - External Output
When streaming, the Frame Rate and Output Size here should match the size and frame rate selected in the Streaming window
For example if you are streaming at 1280x720 at 30fps, select those sizes and frame rates here as well.
Settings - Audio
Master Sample Rate and Master Bit Rate should be set to 48000 and 16 Bit PCM respectively.
When streaming, you can achieve a slightly higher audio quality by selecting 44100 here, but in most circumstances
48000 is preferred.