I have some weird experiences with the speedlite the other day where it was firing a series of flashes on its own for no reasons.
The camera was set on Program mode and I had just finished taking a shot when the speedlite decided to fire on its own.
I switched if off instantly and powered it back on and it's fine again. The same thing happened before and this was the second time I have such experience.
The series of flashes behaves like the camera's built-in flash auto-focus assist lamp. Was there any particular reason why the speedlite would do that?