Denon HEOS Link Owner's Manual page 11

Contents Setup
L Analog Line Input (LINE IN)
Used to connect audio devices with a stereo RCA cable.
(v p. 14)
M AUX Input (AUX IN)
Used to connect audio devices with a 3.5 mm cable. (v p. 14)
N Connect Button (CONNECT)
Used for Wi-Fi setup.
O Connect in Status LED
Indicates the status of this unit. (v p. 47)
Use Troubleshooting
11
Status LED Appendix