Why is my guitar amp not working?

So i got this amp back when i started playing and it stopped working until i got really into it. It's a Crate GLX15 guitar amp that never got turned up high so it's not like i blew the speaker. It just randomly stopped working. Since then it's been sitting in my room. Now several years later i was looking at it because i recently broke a different portable amp i had and figured i could get this one fixed for much cheaper or by myself. Enough history, this is my analysis: The power works because all the lights still work, the input works because it has a tuner that still picks up what notes i'm playing, the speaker however produces absolutely no sound so i figure maybe a wire got broken loose or something. REAL help would very much appreciated.