# Set Preview Input

| Message              | Description                                                                | Arguments |
| -------------------- | -------------------------------------------------------------------------- | --------- |
| `/mixeffect/preview` | Sets the video source of the preview input on the selected Mix Effect Bus. | Multiple  |

| Argument  | Type    | Description                                         |
| --------- | ------- | --------------------------------------------------- |
| Source ID | Integer | Integer that is the video source ID.                |
| M/E       | Integer | 1-based index of the Mix Effects Bus. Default is 1. |


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