Mutify is the best Spotify ad silencing app you can get. That is completely free and works in the background.
Whenever Mutify detects an ad is playing on Spotify, it helps you turn down the volume of the ads automatically, so that you can sit back and enjoy listening to your favorite music without worrying about those annoyingly loud ads.
• Please add Mutify to battery saving exceptions list to make sure it works uninterruptedly in the background (optional)
★ Simple and Clean User interface app while respecting user's privacy.