Can't control volume on JVC MX-D402 system

Control knob is going out try opening and spay with contact cleaner

Bad volume pod

You probably have a bad volume up control switch.

When the volume control is adjusted it sends a signal to a small black box called an IC. This adjust the levels and power going to the main amp of the unit. The IC can be found by tracing the wiring from the volume control back to a printed circuit board.

It's very simple even if you don't have the owners manual.
Step 1: Hold in the Menu button until "DEMO" shows on the display screen.
Step 2: Scroll with the volume knob until it says clock. Then press the volume knob to select it.
Step 3: Scroll with the volume knob until it says "CLOCK SET." Then press the volume knob again.
Step 4: Then adjust the hour first by scrolling with the volume knob. Once the correct hours shows press the volume knob and it will move on to the minutes.
Step 5: Once the hour and minute is chosen push the menu button again to finish the procedure.

The contacts in the volume control encoder are dirty. If you know what you're doing, it can be taking apart and cleaned, otherwise replace the volume control.

Press and hold 'SEL' press down arrow until CLOCK H is displayed rotate Volume knob to adjust press down arrow once to display CLOCK M rotate Volume knob to adjust press 'SEL' to finish. Reference pages 6 and 10 in this link to your JVC KD-G120 Instructions Manual.
http://resources.jvc.com/Resources/00/00/91/GET0330-001A.pdf

Hi there. Sorry I haven't got a solution. Just want to know if you found one, as I got the very same prob with the volume knob of my JVC hi fi. Thanks for your time.

lower the volume of the cd player

i had the same problem but i went to adjust settings and it says right speaker left speaker and you have to set them on ten