From the manual:
Mode / Menu
Press the MODE/MENU button (7) to switch to radio mode or auxiliary input function.
Press and hold the MODE/MENU button (7) to choose the following menu list:
Audio Adjustment
BAS: Adjust the Bass level from -7 to +7.
TRE: Adjust the treble from -7 to +7.
BAL: Adjust the speaker output balance between L7 (left) and R7 (right). BAL 0
indicates an equal balance between the left and right speakers.
FAD: Adjust the speaker fade between R7 (rear) and F7 (front). FAD 0 indicates an
equal balance between the rear and front speakers.
Use the VOL +/- to make adjustments in each menu item
Liquid Crystal Display (LCD) Back Light
Dimmer: Adjust the brightness of the LCD from LIGHT 9 (brightest) to LIGHT 0 (off).
https://www.jensenrvdirect.com/downl...ser_manual.pdf