Guild Wars 2

I have sigil of fire and sigil of accuracy in my sword/pistol and on swap I have sigil of energy in bow, but I feel that it has something like 50% chance to proc on swap – sometimes it gives me energy, sometimes not.
Any opinions and ideas why is this happening?

Sigil of fire is on cool down when u swap. Currently all sigils with cool down share cool down. Fix coming next big patch.