I know this sounds pretty mundane, but there is a terrible mumble to my voice that is an incredible detriment to my social and professional life. No matter how hard I try to communicate clearly, I usually have to repeat what I say because it's so slurred or indesipherable. I get very stressed and withdrawn as a result.
My speaking voice isn't always like this; it seems to vary with my emotional state. When I am excited or when I discuss things that interest me, my voice is just the opposite - as clear and malifluous as a professional orator! But once the ardor dies down, so does my voice's clarity.
I have no idea what to do. I was once a classically trained baritone (ironically, I wasn't too bad), so I'm pretty familiar with ways to improve my diction and enunciation (full vowels, crisp consonants, loose jaw, etc.), but focusing on speech technique always burns me out when I try to talk with people, and I always end up lapsing into a mumble in a short while. I haven't achieved any long term success in getting a clearer speaking voice. So is speech therapy out of the question or not? I'm pretty damned confused at this point, and would appreciate some advice.