The FJ-X3 triggers and the FJ400 strobe have extremely reliable communication. Older technology in the legacy FJ-X2m is good but If you're experiencing issues it is likely related to one of the following:
- Low camera or trigger battery charge
- Improper in-camera menu settings
- Trigger or adapter not seated properly
- Choosing a busy wireless channel
If the connectivity issue is due to high wireless traffic then switch the channels on both the trigger and strobe by an increment of ±5 from the current setting to attempt to find a less-trafficked channel.
You can also use the built-in Auto channel selector. The Auto channel can be engaged by setting both the FJ-X2m trigger and the FJ400 strobe to channel "0" and holding the FJ-X2m trigger's "CH" button on the opening menu for about 3 seconds. The strobe's Channel indicator on the screen will turn green and read "AU" instead of "0". Test fire the trigger to assure connectivity. Auto channel may not be the best choice in heavy wireless environments as the FJ system may make frequent adjustments which result in misfires due to exposures made as the system changes to another channel. At launch, the Auto channel is not compatible with the Canon RT setup. Entering the settings menu of the trigger and scrolling to CH recommended will give you some channel recommendations for quality connections.
If you work often in high wireless which are common with the introduction of 5G phone networks, upgrading to the FJ-X3 triggers with advanced connection technology is suggested.