Might of been mentioned a lot but is it just a bug for me.

Dog just repeats the same phrases CONSTANTLY, had to put it on mute to play it now.

there are a limited number of campanion radom phrases but I've never spent enough time with dog/god or dean for these to get annoying though I usually just take christine with me if I'm going exploring try to mix up your companions

I ran around with God for a while and noticed he kept repeating the same lines over and over.

Lines lines like this one got on my nerves after a while: "I can't believe the idiot swallowed his collar."

...or this one: "It's your own fault you're here, you couldn't leave well enough alone."

Nevertheless, I enjoyed Dog/God more than the other companions by a long shot.

The one that annoyed me was the Ghoul, whatever his name is. The others not so much. But it was more the Ghoul's voice rather than what he said.

BTW, if you go into Options, you can set the Voices level down low without effecting the other sounds. That can help.