How do I prevent sounds from playing?

How do I prevent sounds from playing?

I’ve tried running the /stopsound command in a repeating command block, but that isn’t great because the sound starts playing for a split second then is stopped by the command, creating a split second of noise, which isn’t acceptable.

On my command, I want to have complete silence besides the background noise I’m going to add, and be able to turn them back on with another command. Is this possible?