proline 21 in B200
looking for someone who knows what the little adjustment screws labeled "S" and "T" located next to the pilot and copilot intercom volume control knob are used for. i was hoping they would adjust the squelch since it seems i have to halfways yell for the mic to pick up my voice if it isn't touching my face. the auto squelch doesn't seem to be working properly if there is one.