Multitrack function to automatically reduce volume in a track when audio is playing in another?

I'm currently working with a set of telephone hold prompts. They have background music in one track and several audio clips that play intermittently in another. Is there a way to get the background audio in Track 1 to automatically reduce its volume whenever audio is playing in Track 2? And return to normal when it's playing by itself? I've been setting manual keyframes, but it would be quicker and way more versatile if there was an automatic function.