Subs got quiet??

a few days ago, i noticed that my subs werent hitting as hard as they were. At low volume it does ok, but when i turn the headunit up, it seems as though the subs never get any louder. How do i tell how much voltage is getting to the amp?? Do i hook the dmm up to the red and black rca cables comiong from hu to the amp??

hook the dmm to the power and ground while playing

Quote:

---

Originally Posted by IAD-Zak

hook the dmm to the power and ground while playing

---

Did that. Reads around 13.5-13.8. Now how do i check the signal coming into the amp from the Head unit?? I mean, do teh ss rubicons have anyreviews about the input voltage switch going bad on the amp??