There are two operation modes that are available for video transitions. There is "A/B Mode" and "PGM/PST Mode". To set the operation mode:

1. Make sure that your HDMI preview output is connected
   
   
2. Press and hold the [TAP (BPM)] button for at least 3 seconds
   (You should see the Main Menu)
   
   
3. Use the Transformer [] button to navigate to the Page 3 in the Menu
   
   
4. Select A/B MODE
   
   
5. Use the T-Bar Fader to set it to either A/B Mode or PGM/PST Mode

A/B Mode
The video on the bus toward which the A/B fader is flipped is output.

PGM/PST Mode

Lighted in red: Video currently being output
Lighted in green: Video to be output next

The video selected at the PGM bus A is always  PGM output, and for the PST bus B indicates the video to be output next.

Operating the A/B fader causes the selected video at the PST (bus B) position to be output from the PGM (bus A) position.

* Bus assignments made using EFFECTS [ON] buttons or TRANSFORMER buttons (bus A or bus B) do not change.