CSM Troubles

[Strategia_In_Ultima]

I was just playing a game with/against the AI (I controlled only a single fleet, the ministers controlled the rest of my empire) when strange things began to happen with the CSMs which the AI apparently appointed as being the weapon of choice for my empire.

First, I played a combat replay of an enemy attack (1 ship) on one of my planets. The WP present on the planet only fired one volley of CSMs despite being intact and in range of the enemy ship for like 20 turns.

Then, an enemy fleet of 7 ships attacked a planet cluster (1 planet, 2 moons, all colonized) and I decided in favor of Tactical in light of the event described above. The planet was pretty full of WPs with CSMs. I fired several volleys at the enemy - however, several volleys did no damage at all for some reason.

WTF? CSMs which refuse to fire? Phantom CSMs? What is this?

(Please Note I'm using 1.61 Gold, no mods)