The beeping of cars when the doors are open.
The short blaring of car alarms, when they are closed remotely via key fob, just to make sure they work!
The beeping of bus and train doors when they are closing.
The banging hissing vents of overpressure in the pneumatic tanks of busses and trucks.
The humming and hissing of HVAC for the refrigeration of supermarkets.
The blaring of music in supermarkets (special case: Kylie Minogue with 'Can't Get You Out Of My Head' which somehow seems to be in the eternal Top 20ies of supermarket music. La la la, lall lall, la la la lall lall....), the penetrant marketing displays activating from some endless loop when anything comes near them.
The stupid video walls in stations, blaring uninteresting shortnews, weather, and adverstisements while almost everybody is sunken into their smartphones. Talk about wasted effort!
The same goes for so called information displays in Trains, Subways, Metros, Buses installed every 2nd to 3rd row of seats.
I could, and sometimes do counter that with something playing over my earphones, but i don't like to, because it messes with my situational awareness.