Don't you get tired of people constantly asking you what the hell you just said?
Speak clearly and try to speak at a volume where others can hear you.
You don't have to say "ummm" every time you pause. It's okay to have silence in between words! Trust me, I do it all the time.
If you are blessed with the ability to speak then how about trying to do it efficiently and not half assing it with a baby voice and a retard mumble?!
JesusummmmIhatemmmmmummmblers...