How do you replace a 4 pin HRS connector on a wireless microphone?

You'll need to let us know what brand of belt pack transmitter you are using as the pin configuration on some brands is not standardized. Audio-Technica beltpack pin 1 is ground but same pin on some Vega packs would be Mic (LO Impedance) audio in. If you specify the microphone and the brand of transmitter beltpack we may be able to help. Regards