Why are my subs mking a buzzing noise instead of hitting?

i just had installed 2 12 inch rockford fosgsate p1 subs and a rockfor amp. while i was going down the rad with the radio not even turned up that load the speakers completely shut off and in replacement of the bass came a annoying buzzing noise that wont stop, i checked all the fuse and looked at all the wiring and i can not find what could be wrong with it. i doubt the speakers are blown cause they were just instaslled 3 days ago. they worked great till this happened? can annyone help me fix my problem?