As I exited the interior of Helios-One, where Fantastic was, to get to the solar collectors, I heard metal clanking sounds behind me, and what did I see? The dogs from Gibson's Scrapyard and a couple of molerats all came out the door. I'm not making this up. After I killed them I decided to kill the NCR troops in the area. I used the lever-action shotgun btw, which has serious problems: shortly after reloading I cannot use the iron sights, and the rate of fire seems very uneven. After cleaning up, I saw one of the molerat corpses disappear in front of me. Then I noticed the sound had gone bad: it sounds low-quality and has ''static''. It's the game, not my TV or headset. I sure hope it doesn't persist.

i guess just reload an earlier save, the dog and molerat attack happened to me too