I've had the same Hollywood amp running in my car for years, and all of a sudden it's stopped working.
The car battery shows 12v on the multimeter. When the car is off I get 12v between the positive terminal and ground on the amp. However, when I turn the car on (no problems with the car starting), the voltage at the amp drops to 4v which is insufficient to run it. Then I test between the remote and ground and get 12v.
Is a new battery the way to go? if so any suggestions to which ones remain charged longer for car audio systems