No sound from radio or any chimes on a 2015 Impala.
I am guessing you are asking a question and not just letting us know.
first check to see if you have a fuse or relay for the radio amp that is blown.
do you have water leaking into the vehicle or trunk like the 2014’s were having problems with? if so, you need to trace the wires and look for corrosion or broken wire. I found this as an example. it is not the best video, but you will get the idea.
The chimes may come from the radio, so then if the radio isn’t working, no music, no chimes. Unless there’s a reason to believe otherwise, assume the radio is the problem for both. A shop back-probing the radio’s connectors to verify there is for power & ground to the radio is the first step.