while dreaming, when people talk to me i cannot actually hear their voices. their mouths move and what they say is perceived by me, kind of like i just understand what they’re trying to say. this also happens when i try and speak back — i don’t actually say it outloud, it’s almost like i’m thinking of it and they just understand. i was wondering if anyone else experiences this?
Yes, it happens to me as well, though not all the time. I tend to “speak” back in the same way. I communicate with animals in lucid dreams this way.
Yeah, I have this sometimes too in my dreams.
and welcome, btw 
this is actually kind of common, DC’s, as part of you mind, well, most of them can read your mind.
you think of something to say to them, and they reply without you saying it.
its happened to me alot of times.
For me it really depends on how deeply i am dreaming, be it lucid or not. If it is a pretty light sleep usually it is that way for me, however i find the deeper it is the more “real” it gets. This was actually one thing that really helped me in the past when i used to LD alot. I would actually use this as a dream sign.
I actually have experienced that many times before. I think that’s how I communicated to DC’s in a LD once. It feels really strange, but It is kinda cool
In my last LD, i asked from a DC who attacked me: “Who are you?” repeatedly. Although (s)he replied continiously, i was unable to hear her/his voice. The same continued even if i took away my “dream earmuffs”, and tried to keep my ear close to her/him. Unfortunately i wasn’t able to track what (s)he wanted to say.
I haven’t communicated much in my dreams. But every time is different from the other. Talking, telekinesis, I think I’ve even done some kind of body-language.
There have been a few occasions where I could recall what had been said to me. Just a sentence or two and usually some sort of advice. Such as my grandfather telling me how to be a good person. Or a girl saying, “There’s getting to know somebody and then there’s being comfortable” as she slowly slips into my bed.
This happens with me a lot. Usually, unless in some really specific cases, I don’t remember the DCs actually speaking, but I still know what they “said”. Thus, I rarely recall any voices, though I recall what was said. I guess either my dreams are silent or I’m just more visual 
try to ask questions to a DC while your mind is clear and thoughtless (like a meditative state), so you’d only expect a detached response from the character. so it seems you would have to go from being aware your dreaming to pretending its real for the effect of being uncertain for once in a dream. could there be a subconsious in a dream?
maybe ask a question each time, by reciting your question as a mantra, just so its a thoughtless Q and you can focus on relaxation.
i donno try it see what happens