You might also want to record yourself when talking normally to friends and family. It may be partly a lack in voice change but, like Dena said, it can also be partly because you are more expressive when you speak than a cis guy usually is. I have found that the more monotone-ish you speak, the more people think of you as male. Recording yourself while having normal conversations will help you to recognize in what circumstances you tend to talk in a less masculine way. (Though I totally know the feeling--my voice is what I hate more than anything. I can't STAND to listen to recordings of myself because I sound so much lower to me than I do to other people!)
