Volume People have complained that they can't hear me when I am on the phone even though the volume is up as far as it will go. We didn't have a problem with the phones (we have three handsets and all of them seem to have this problem) for the first year we owned them, so we don't know what might have changed.

SOURCE: How is ringer volume adjusted?

VOLUME
While talking, press the VOLUME buttons (left and right
arrows) to control the volume of the handset's earpiece.
There are four volume levels. Press the right arrow (+)
button to increase the volume level, and press the left
arrow (-) button to decrease. VOL 1 is the lowest level and
VOL 4 is the loudest.

SOURCE: How is ringer volume adjusted?

the ringer is too loud and the beeps from pressing the buttons are too loud.