I've been having this problem very consistently lately with almost all my lucid dreams. I've always found verbal commands to be very helpful for me, but lately when ever I try to say something it comes out as a little squeak. If I try too hard to force myself to talk normally, I wind up awake, in my bed, saying it out loud to myself (not a false awakening, I've been doing reality checks.)

I'm not sure how I can fix this, and I was wondering if anyone else had any suggestions.