The second curtain setting is found in the menu section. Scroll to ‘SYNC’ and it is the 3rd option right under the “H” symbol.

Firmware Version Checking:
Please switch the transimtter off, then press the “MODE” button and hold
down. Turn thetransimtter on, and the firmware update version (e.g. Version 10 will read U-10) will
be displayed on the LCD panel.

Firmware Version Checking:
Please switch the receiver off, then press the “GR” button and hold down.
Then turn the receiver on, and the firmware update version (e.g. Version 10 will read 10U) will be displayed on the LCD panel.

Please update to the latest version of the Godoxphoto App and the issue should be solved.