Why is my earbud volume super quiet?

My iPad sound is normal without earbuds, but when I plug my earbuds in and turn the volume up all the way the sound is whisper quiet. These earbuds work just fine with other devices, so I’m not sure what the problem is. I have confirmed that my iPad is sending sound to the earbuds and the earbuds are all the way plugged in. Turning them makes no difference. Thanks!