I got Siemen hearing aids, Model LS-C, for both ears from VA about 8-9 years ago. At the time, the ear doctor used a digital machine to adjust the upper/lower tone levels to my comfort...but I have since sent them both to VA for cleaning/servicing and when they came back, they worked great BUT the original tone adjustment was defunct and the pitch was way too high for my comfort. What's required to reset them back to my comfort zone??