If your TV is playing sound through the wall, it's likely because the sound is bouncing off the walls and into your neighbor's apartment. There are a few things you can do to reduce the amount of sound that escapes from your TV:
1. Use a soundbar or external speakers. Soundbars and external speakers will direct the sound away from the walls and towards your viewing area, reducing the amount of sound that escapes.
2. Adjust the audio settings on your TV. Many TVs have an auto-volume feature that adjusts the volume based on how much ambient noise is in the room. Turning this setting off can help reduce the amount of sound that escapes from your TV.
3. Turn down the volume on your TV. This one is self-explanatory - if you turn down the volume on your TV, less sound will escape from it.
4. Move your furniture around. If possible, try to move your furniture so that it isn't directly up against any walls. This will help absorb some of the sound before it has a chance to bounce off the wall and escape into your neighbor's apartment