One of these days you may see me with a black eye!! But here are my selection of things that I use to respond to to much noise. For a start, I do look at the floor in any new cafe I plan to enter. The hard floors with no sort of covering, means that the sounds do resound more. Then I do look to see if there are speakers close to a particular table area and choose somewhere well away from it if possible. Once I am sat down, if the music is loud, I will order coffee or food and follow that by asking " and will you turn the music down please" If they say they are not allowed to, I get up and say very well just cancel my order and leave. If it is the kind of place with a couple of rooms, I will ask if they are able to turn the sound down in one room, although of course often the sound is the same in both rooms. You might enjoy the particular one I remember.
I was travelling to London to sing in a concert. and had booked a seat in the QUIET carriage. I had a walkman in those days and had it on quietly specifically going through my line . The carriage was not very busy and most people were doing their own thing, when this man proceeded to plonk himself down with his computer, use it leaving all the sounds on quite loud with beeps etc etc , and then started to speak loudly on his phone to someone, and mostly of no importance about whereabouts we were on the journey and what they would be doing etc. I put up with it for a time as we can all be caught out by a phone call, but when the voice got louder and no attempt was made to be quiet. I got up , went across and said could you keep your voice down please . This is the quiet carriage and everyone is trying to do their own work. He just shrugged and carried on. I then sat in a seat nearer to him and as he continued to talk at the top of his voice I began to sing in italian from an opera. He stared at me and was silent for a moment. I immediately stopped singing. He began again and so did I . He glared at me and said what do you think you are doing? I replied "working the same as you" He tried once more and then flounced off to another carriage. I returned to my seat quietly and no more was said, until a rather nice elderly lady came past on her was to get off and thanked me !! I hasten to say I have never had to repeat the performance.