iPazzPort KP-810-19R/19VR - Manual (Page 18)

2 Change audio output settings: when pluging USB receiver into USB
port on the computer system will set wireless audio HID device as
default audio output device, and you only can hear sound from computer
by the wireless keyboard, So if you want to set other audio device as
output device, please follow below steps to change its settings:==>
start==> settings==>control panel==>sound,audio and devices ==>
change speaker settings, in the following popup window, please
change the default audio output device to other output device,
for example, if your device is Realtek HD Audio,please select Realtek
HD Audio Device. Please re-start your player to enjoy music.