blowing fuses

louis1965

I have a sub madel LR106476 that have worked fine for 4 years and all of a sudden stopped working,i opened it up today, and found a blown fuse,i replaced the fuse with a 1.5 amp i cant read the amp size for sure but looks like a 1.5. anyway with the new fuse it blows as soon as i plug it in,the speaker makes a humming noise and the fuse blew and only did it once two more fuses and it blows right away. any ideas?