Another strategy, if it is too loud to hear the server, especially the specials, hand the server a remote blue tooth mic if you have one that works with your hearing aids. My husband and friends are also good about telling me about specials they know I'd be interested in. Or I ask the server to come over and tell me individually due to a hearing loss. Of course it can be too loud to hear even then!
Also use (or get) a speech in noise program on your hearing aids. I keep having my audiologist tweak my hearing aid programs, trying to find the best way to hear in noise – which is everyone's major problem and one the hearing aid manufacturers have not really solved, though they are making some headway. When I upgraded to my Oticon Opn, for the first time I could hear the server in a loud BBQ restaurant we liked.
When you make reservations, ask for a quiet area due to hearing loss. It sometimes helps. I put this on Open Table reservations. Be specific if you know the restaurant. I have one friend who finds the quietest table, then finds out what the table number is that the servers use. She uses that information when making reservations to be sure she gets that quiet table each time. I might ask for a booth or sometimes for an outside table which can be quieter.
As you can tell, I eat out a lot!