I often wonder this myself. For me, a hard of hearing person, or someone with some deafness, I never really hear what is being said. I can hear the speaker but I always assume they are asking, "Good afternoon. What would you like to order today?
What are your experiences? How do you order food at the drive through?
Below is a video about a company, Order Assist, with a mission to install a type of machine that can help many people with communication issues (deaf/hh, speech disorders, etc.) order food effectively at the drive through. I am not hopeful that many fast food restaurants will be willing to use this service. I guess if there is a restaurant who is aware that most of his customers are deaf/hh or have some sort of communication issue, then maybe they would think about using this service.
I think it is a great idea. But, I think the best thing would be to make the drive though accessible for all by including a touch screen menu and then if someone needs help they can push a button to call or type a message.