If you have a RS-600 pack  that “appears to bebroken”  Examples: -         Itwill not let you turn on or off the microphone-         Perhapsyou can get to channel A but not B. Sometimes, it is nothing more than a beltpack having been miss-programmed. If you restore the beltpack back to the factory default, the problem (s)may vanish…    To restore the factory default settings for all four modes: 1.   Press and holdthe setup button until the setup information window displays a “P” and thenrelease the button. 2.   Press and holdthe Call A button. The display changes from “1” to “2.” 3.   While stillholding the call button down, press the setup button. The display momentarilyshows an “F” to indicate that the beltpack is now programmed with the factorydefault settings. 4.   Release thesetup button and the call button. 5.  The beltpackresumes operation with the factory default settings.