How do I bring my sound back? I have somehow muted my clips.

Justinkredible1

I have a few patterns that I have created in different groups, I tried adding a new sound to another group and now the other sounds are not playing. The patters are still there and it is moving through the track, but I can not hear any sound anymore. I have tried the mute button, solo button and played around with the mixer, but nothing is working. This has happened to me a few times when I have added a new group with different sounds. I have so many projects that I have made that I can no longer hear and don't know how to fix this problem. I have also tried the undo button, but it also does not work.