The Guardian:

So, even though we may be surprised by the “Mickey Mouse” quality of what we actually sound like, it is the extralinguistic content of what our voices may reveal that could be more disconcerting. Yet it is unlikely that others are similarly surprised by a high-pitched aspect of your voice, and moreover others probably aren’t making the same evaluations about your voice that you might. We tend not to be critical of other people’s voices, so the chances are you’re the only person thinking about your own.