if you have all the flashes connected to the dropController why not link them all to a single flash trigger port. This can be done fairly easy with Y connectors or a simple flash trigger multiplier device. Have a look at the recently updated “Adding More Flashes (Flash Trigger Multipliers)” post (https://www.dropcontroller.com/adding-more-flashes-flash-trigger-multipliers/)
The Flash Trigger ports are not really designed to trigger multiply flashes at the same time. The extra ports are from when I was experimenting with different triggers and multiple exposures.
It may be worth while checking your flashes for timing errors. I had a similar experience with my flashes and it turned out one of them had started firing a little bit later than the others.
- This reply was modified 6 months, 3 weeks ago by Martyn.