Symptoms: Ear piece volume is low even though it has been set to its highest level.
Possible Answer:
Try turning the Noise Cancellation setting to OFF and when you make a call, turn the volume up as far as it goes.
If this doesn't work there is a hearing aid mode which you can turn on (This then allows you to increase the volume further) but this does turn off the ability to turn off the noise cancellation, so try that one first!