All Panasonic system phones have a volume control, navigator
button, or jog dial.
If your phone has an LCD display, press the middle button beneath
the word RING (or RNGOFF) on your display...
then if your phone has a volume control or navigator button, press
up or down to adjust the ringer volume. If your phone has a jog
dial, roll it clockwise or counterclockwise to adjust the ringer