Question: 
1. Why does my local headset mic level of a Basestation always show "Dynamic" when a headset is plugged in? With no headset plugged in it always shows Electret mic ? How do I change it?
2. Why does my headset mic level of a Beltpack always show "Dynamic" when a headset is plugged in?  With no headset plugged in it always shows Electret mic ?  How to change it ?

Answer:  The 4-pin XLR male headset connector mates with most Dynamic or Electret headsets that have 4-pin XLR female connectors.  This Headset connector allows a user to communicate in “Dual-listen” or “Single-listen” mode on either intercom channel.  The mic detect circuit (dynamic/electret) will indicate dynamic when it sees a load of 600Ω or less. It will indicate an
electret when it sees 1kΩ or greater. Between 600Ω and 1kΩ is not recommended as it may not accurately detect mic type. 
These are simply default settings. The actual circuit will sense the correct mic type when connected to a headset. There is no need to change anything, this is normal operation. Also you cannot adjust the Mic level without a headset connected.