Jump starters have internal circuitry to limit the charging current and to prevent over charging. This is necessary due to the jump starter usually being powered by a sealed lead acid battery, which can be somewhat "delicate" in some respects.
I expect there is a problem with that internal circuitry...
Hello matomeIts sound like you have dirt, dust, some kind of containments in the volume controls of the unit are their separate vol controls for left and right id say if you could try some electronic spray contact spray and as you spray have maybe another person help you by working all the volume knobs full right full left or full up and or full down, If this help but doesn't solve you may need to remove and expose the circuit board inspect for loose or cold solder joints..Im not sure your make model year etc, But dollars to doughnuts most likely that would be my next plan off attacking the problem. Well im so sorry I hope this helps or at least leads you down the right path.sincerely, Robert
