What dictates others actions in a dream?

So from what I've collected over the years, the way I understand it is that DC's are projections of your own subconscious, such as if your dreaming about talking with your parents, they will react like you think parents normally should. However, some of the things said by DC's are just totally off the wall, like stuff that you would never picture them saying, or like you just can't understand their intentions on where they're coming from. Or take this for example. You're dreaming of laying on your bed, waiting for your girlfriend to call. You dream that you lay there for 30 minutes before the phone actually rings. What triggers this to happen? Why did it not ring after only 10 minutes? You wholly believed the whole time that it was going to ring any minute now. Is it just completely random and chaotic?

I think that there's a definite chunk of it that at lease seems random. As for how people you know acting like they would in real life, that could be more of a projection of how you have seen them act in the past mixed with the general dream weirdness. As for what causes the weirdness, seemingly random bit, I'm not sure.

Maybe the seeming random craziness is actually your subconscious mind trying to communicate with you symbolically. Symbolism is a large part of dreams, at least in theory, and many believe that your subconscious mind basically tries to show you things about yourself that your may not consciously be aware of--be they fears, emotions, stressors; so my guess would be those are symbolic references to something you either feel/think/believe/worry about and your mind is trying to tell you this.

~SilverWolf~

As soon as you expect randomness and weirdness doesn't it become a self-fulfilling prophecy?

Or what about say if you were talking to a friend in a dream, and they bring up the subject of soccer. What made them bring that up over the subject of television? Or what about if your listening to your iPod in a dream, it's on shuffle with 7000 songs on it. What causes the Pink Floyd song to come on as opposed to the Beach Boys? There's just gotta be some rhyme or reason to it, but I just can't figure it out.

Something to do with synchronicities maybe? I really hope there's an answer out there, it's driving me crazy!

Another question: what makes you think of soccer in real life?
Surely watching it, but you don't have to see it to talk/think about it. It's the same with dreams. Sometimes you just come up with random things, and since DCs are part of you, well, they can too. And there is the general dream weirdness that other people mentioned. Anyway that's what I think.
As to what exactly triggers thoughts about a particular subject, I'm afraid I don't know, maybe Google would help here.