Audio / MP3 music: ESP8266 + DFRobot DFPlayer Mini + Music Player widget + Wifi (NodeMCU, Wemos D1, ..)

Hello. I am new here.
I followed the instructions and am unable to get the player to play anything.
I have the player TX and RX setup on D6 And D5
Using the NodeMCU 1.0 (ESP-12F-Module)
Can someone help. What more info do you need?