Chances are the hardware was damaged from the fall...either a broken speaker, disconnected terminals, to even damaged sound processing.
You might want to run a hardware test to see if the speaker is still working or not. This from another site on how to run that:
6. Engineering Mode *#*#2486#*#*
If code does not work, turn off your phone. Hold volume up, volume down and power key at the same time for few seconds. You will be redirected to Fastboot Mode, then navigate (volume down) to "BP Tools" and select it by pressing power button. Your phone will reboot into system. Now, you can try select secret code again or open CQATest app in app drawner - it will appear after reboot.
https://www.hardreset.info/devices/m...neering%20Mode
