message: Example AudioPassThru_wEarpieces: added text describing trouble-shooting if you can't hear anything
diff: * example, we strongly recommend that you use the EarpieceMixer. For an example, of the
  * EarpieceMixer class, see "TrebleBoost_wComp_wEarpieces_wApp"
  *
  + * BE AWARE: Since this example has no amplification, it sounds very quiet if you listen through
  + * the earpieces. Very quiet. If you cannot hear audio through your earpieces, please consider:
  + *
  + * * Plug headphones into the headphone jack of your Tympan or of your Earpiece shield. Rub
  + * the earpiece mics with your finger. Do you hear it through the headphones?
  + *
  + * * Listening through the earpiece again, rub the earpiece mics with your finger. Do you
  + * hear it through the earpiece? Try unplugging the earpiece from the Tympan to really
  + * hear what it sounds like unampflied. Then, plug the earpiece in and listen again?
  + *
  + * * Try turning up the output loudness on the Tympan (ie, add some gain!). Find the line
  + * "earpieceShield.volume_dB(0.0);" Change the 0.0 to 10.0 or even to 20.0. That'll add
  + * a lot of gain. Because you've added gain, it's no longer "AudioPassThru", but you
  + * should more easily hear the output.
  + *
  * License: MIT License, Use At Your Own Risk
  *
  */
  