Remove the speaker load. If this does not solve the problem then your amp may be damaged from being connected to too low an impedance. Make sure your amp is capable of driving the speaker load you have connected to it. Ohms is a measure of the speaker's impedance. Lower ohms means higher load on the amp. Using a speaker with 4ohms is safe for car amplifiers, some can do 2ohms but very few can safely do less than that. You didn't specify the model but I'm guessing that all JL amps will do 2 ohms no problem.
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Remove the speaker load. If this does not solve the problem then your amp may be damaged from being connected to too low an impedance. Make sure your amp is capable of driving the speaker load you have connected to it. Ohms is a measure of the speaker's impedance. Lower ohms means higher load on the amp. Using a speaker with 4ohms is safe for car amplifiers, some can do 2ohms but very few can safely do less than that. You didn't specify the model but I'm guessing that all JL amps will do 2 ohms no problem.