The Laugh Response

I do not know if I have bad hearing or if I am just prone to meeting mumblers, but whatever it is I can never hear what people are saying. I can hear what my friends are saying. Maybe once I become friends with someone they get louder. Anyways, when I first meet people its automatically awkward because that is my lifestyle. So when I meet someone and they say things and I cannot hear what they are saying, I either say what about a million times or give the laugh response. I choose the laugh response 9 times out of 10. If I truly am concerned with what you actually said I will possibly say what but for some reason I get awkward and can't manage to say what or just don't care so I laugh and hope that what they said was funny. I do usually start out saying what but I'm not going to say it every ten seconds so I just pretend to hear you. This is really stupid of me yet I do it all the time. I am mentioning this because I was recently caught. This new man that I met asked me a question. All I heard what "so youdsgjkhhsdglsgkjs" so I responded, "hehahehheh" Then he said "what?" because he asked me a question. I guess that is better than if he said, "My grandma and cat died today" because then I would just look like an ass. In this situation I just looked like a superfreak and I probably will not be talking to this man any time soon.
In conclusion, please speak more clearly and if you are not good at doing so, please understand that I will not always say what, I will have no idea what you are saying to me, and I'm not a superfreak when I laugh at your questions.