Low volume

It started about 2 to 3 weeks ago. The volume on my directv is SO low. I have to turn it up to 30 or above when I used to be able to watch it at 12 or 14, But if I go to an app like Netflix, the volume blows you out of the room, it is so loud So I know it's not my TV. This only affected one of my TVs, Directv, please fix this as it's driving me crazy.