Vladimir cycles the action on an M-16/M4 that had previously been used. This is pointless, as the the firearm is an auto-loader, and would have already had the chamber loaded.
Vladimir asks Daredevil if he has heard of "Leslie Shumway" and identifies him as Al Capone's accountant. However, Al Capone's accountant, who eventually testified against Capone, was Louis Shumway.
When Daredevil and Fisk are speaking to each other, they are using standard 2-way police radios - call and response. You never see or hear them actuate the call buttons. They speak as if they are talking on the phone.
When Karen calls Matt from the hospital, you can see she's not really on the phone because the green dial button is visible.
It makes no sense for Daredevil to be blamed for the three officers being shot. The shots were clearly fired from a different building that the one in which Daredevil had initially taken refuge. The Detective appears to be facing away from the building house Daredevil when he is shot; same as the two officers. As a result Ben Urich should have realized that Daredevil could not have killed those police officers.
When the Russian gangster is about to die his voice fades and he whispers the name of Fisk's accountant. Daredevil has to lean in to hear him. Having the ability to hear things clearly even a block away would mean that he would not have to lean in close to make out what is being said before getting head butted.