TV/Music Audio to speakers question

I have a TV that I set up outside to watch sporting events. When at bars and the barber shop I noticed the speaker audio change from the tv sound to music during commercials, then when the game comes back on the audio switches from music back to the game. I was told it has to do with getting an amp with 2 inputs, but I’m not sure how to go about this. I would like to try and get this sort of automatic switch setup for home use. Is this possible? Any insight would be greatly appreciated!